Last updated: October 22, 2026
Cheerio bars are chewy, buttery cereal squares made by melting butter and marshmallows, folding in plain Cheerios, and pressing everything into a pan. The recipe card sits below, and this walkthrough covers every detail so your bars set up soft instead of stiff.
Cheerio Bars Ingredients and Equipment
Cheerio bars need just five ingredients: Cheerios cereal, mini marshmallows, unsalted butter, vanilla extract, and fine salt. A large pot, a 9×13-inch baking pan, and parchment paper are the only tools that matter.
Cheerios Cereal
You need 6 cups of plain Cheerios, which is enough to coat evenly without drowning the cereal in marshmallow. Original yellow-box Cheerios give the cleanest toasted oat flavor and keep the bars from tasting too sweet.
Use a fresh box if you can. Stale cereal turns chewy in the wrong way and takes on a cardboard note once the marshmallow hits it.
Mini Marshmallows
Use one 10-ounce bag of mini marshmallows, which is about 5 cups. Minis melt faster and more evenly than full-size marshmallows, so the mixture turns smooth in a few minutes with no stubborn lumps.
Fresh, soft marshmallows matter more than anything else in this recipe. A bag that feels hard or crunchy has dried out, and it will give you bars that set up tough.
Unsalted Butter
Measure 1/4 cup, or half a stick, of unsalted butter. The butter keeps the marshmallow loose and glossy as it cools, and it adds the rich flavor that makes these taste like a real treat instead of plain sugar.
Unsalted butter lets us control the seasoning. If you only have salted butter, skip the added salt.
Vanilla Extract and Fine Salt
You need 1 teaspoon of vanilla extract and 1/4 teaspoon of fine salt. The vanilla rounds out the sweetness, and the salt keeps the marshmallow from tasting flat.
Stir both in after the pot comes off the heat. Vanilla loses its fragrance when it cooks, so adding it at the end keeps the flavor bright.
Pan and Tools
A 9×13-inch metal or glass baking pan gives you bars about one inch thick, which is the sweet spot for a chewy bite. Line it with parchment paper and leave an overhang on two sides so you can lift the whole slab out for clean cutting.
You also need a large, heavy pot that holds at least 4 quarts, plus a wooden spoon or silicone spatula. A bigger pot makes folding the cereal much easier and keeps pieces from cracking.
How to Make Cheerio Bars
To make cheerio bars, melt the butter over low heat, stir in the marshmallows until smooth, mix in the vanilla and salt, fold in the Cheerios, and press the mixture into a lined pan. Hands-on time is about 15 minutes, and the bars set in 30 minutes.
Prep the Pan First
Line the 9×13-inch pan with parchment paper, leaving a few inches hanging over two opposite sides. Rub a little butter over the parchment so the bars release easily later.
Measure the Cheerios and have them ready next to the stove. Marshmallow stiffens quickly once it cools, so everything should be within reach before you start melting.
Melt the Butter and Marshmallows
Melt the butter in the large pot over low heat, then add all the marshmallows at once. Stir constantly with a wooden spoon for about 4 to 5 minutes, until the marshmallows are completely melted and the mixture looks smooth and glossy.
Keep the heat low the whole time. Marshmallow scorches fast, and overheated marshmallow turns into candy that sets rock hard.
Add the Flavor and Fold in the Cereal
Take the pot off the heat and stir in the vanilla and salt right away. Add all 6 cups of Cheerios and fold gently with a silicone spatula, scraping the bottom of the pot, until every piece is coated.
Work quickly but gently. Folding rather than stirring hard keeps the cereal whole, and whole rings give the bars their tender bite.
Press and Set the Bars
Scrape the mixture into the prepared pan. Butter your spatula or a square of parchment and press the cereal into an even layer, using light pressure instead of packing it down.
Let the pan sit at room temperature for 30 minutes until the bars are set. Do not use the refrigerator, because the cold makes marshmallow bars firm up too much.
Cut and Serve
Lift the slab out of the pan using the parchment overhang and set it on a cutting board. Cut it into 16 squares, four rows by four rows, using a lightly buttered knife so the marshmallow does not drag.
Serve the bars the same day for the softest texture. They pack well for lunchboxes, bake sales, and road trips because they hold their shape without frosting or filling.
Tips for Soft, Chewy Cheerio Bars
The biggest secret to soft cheerio bars is a gentle hand and low heat. Gentle pressing and gentle melting give you a chewy square instead of a dense brick.
Use Low Heat and Stay at the Stove
Low heat melts the marshmallows slowly and keeps the mixture from caramelizing. If the marshmallow starts to turn tan or smell toasty, the pot is too hot and the finished bars will be hard.
Do Not Compress the Cereal
Packing the mixture firmly squeezes out the air pockets that make a bar tender. Press just until the top is level and the corners are filled.
Butter Your Tools
Marshmallow clings to everything it touches. A little butter on the spatula, the parchment, and the knife keeps cleanup easy and your hands clean.
Cheerio Bar Variations and Substitutions
Cheerio bars welcome easy add-ins, but the recipe card keeps the base simple, so treat everything in this section as optional. Add any mix-in after you fold in the cereal, and keep the total to about 1/2 cup so the bars still hold together.
Peanut Butter Cheerio Bars
Stir 1/4 cup of creamy peanut butter into the melted marshmallow before adding the cereal. The bars come out richer and a little softer, with a salty peanut flavor that kids love.
The card leaves this out, so use it only if everyone eating the bars is fine with peanuts.
Chocolate Chip Cheerio Bars
Let the mixture cool for 2 minutes after folding in the cereal, then stir in 1/2 cup of mini chocolate chips. Waiting keeps the chips from melting into streaks, so you get little pockets of chocolate in every bite.
Honey Nut and Other Cereals
Honey Nut Cheerios make a sweeter, more caramel-flavored bar, and they work as a straight swap for plain Cheerios. Keep the 1/4 teaspoon of salt, which balances the extra sweetness.
Festive Add-Ins
Colorful sprinkles, mini candy-coated chocolates, or dried cranberries turn cheerio bars into a party treat. Fold in sprinkles at the very end so the colors do not bleed into the marshmallow.
How to Store Cheerio Bars
Store cheerio bars in an airtight container at room temperature for up to 3 days. Place a sheet of parchment between layers so the squares do not stick together.
Do not refrigerate them, since the cold turns marshmallow stiff and dry. Do not leave them uncovered either, because open air makes the surface hard within hours.
Where Cheerio Bars Come From
Cheerio bars belong to the marshmallow cereal treat family that started with the Rice Krispies Treats of the late 1930s. Home cooks quickly swapped in whatever cereal sat in their pantry, and Cheerios, which General Mills first sold in 1941 as CheeriOats, became a favorite thanks to their mild toasted oat flavor.
Today they are a staple at school fundraisers, potlucks, and after-school snack tables. The sturdy rings stay a little chewier than puffed rice cereal, so the bars feel heartier than the classic version.
Use the recipe card below to print or save the full cheerio bars recipe.
Chewy Cheerio Bars
Soft, chewy cheerio bars made with butter, mini marshmallows, and plain Cheerios cereal, ready in 15 minutes of hands-on time.
Ingredients
- 6 cups plain Cheerios cereal
- 1/4 cup (4 tablespoons) unsalted butter, plus more for greasing
- 1 (10-ounce) bag mini marshmallows (about 5 cups)
- 1 teaspoon vanilla extract
- 1/4 teaspoon fine salt
Instructions
- Line a 9x13-inch baking pan with parchment paper, leaving an overhang on two opposite sides, and rub the parchment lightly with butter.
- Measure the Cheerios and set them next to the stove.
- Melt the 1/4 cup butter in a large pot (at least 4 quarts) over low heat.
- Add all the marshmallows and stir constantly with a wooden spoon for 4 to 5 minutes, until completely melted and smooth.
- Remove the pot from the heat and stir in the vanilla and salt.
- Add the Cheerios and fold gently with a silicone spatula, scraping the bottom of the pot, until every piece is coated.
- Scrape the mixture into the prepared pan and press it into an even layer with a buttered spatula or parchment, using light pressure and not packing it down.
- Let the bars set at room temperature for 30 minutes.
- Lift the slab out using the parchment overhang and cut into 16 squares with a lightly buttered knife.
Notes
Store cooled bars in an airtight container at room temperature for up to 3 days, with parchment between layers. Do not refrigerate.
Keep the heat on low, because overheated marshmallow sets hard.
Use fresh, soft marshmallows. Skip the added salt if using salted butter.
Optional add-ins not included in the ingredient list: 1/4 cup creamy peanut butter stirred into the melted marshmallow, 1/2 cup mini chocolate chips folded in after the mixture cools for 2 minutes, or sprinkles folded in at the end.
Nutrition Information:
Yield:
16Serving Size:
1 barAmount Per Serving: Calories: 120Total Fat: 4gSaturated Fat: 2gSodium: 125mgCarbohydrates: 22gFiber: 1gSugar: 13gProtein: 1g
Cheerio Bars Questions and Answers
Why Are My Cheerio Bars Hard?
Hard bars almost always come from too much heat or too much pressure. Keep the burner on low, take the pot off the heat before adding the cereal, and press the mixture lightly into the pan.
Can I Use Large Marshmallows Instead of Minis?
Yes, but they take longer to melt and are harder to stir smoothly. Cut them in half with buttered kitchen scissors, use the same weight, and keep the heat on low.
Can I Make Cheerio Bars Ahead of Time?
You can make them up to 3 days ahead if you store them airtight at room temperature. Cut the bars just before serving if you want clean edges.
Can I Double the Recipe?
Yes, make two separate batches and press each one into its own 9×13-inch pan. Doubling in a single pot crowds the cereal and makes it hard to fold gently.
Are Cheerio Bars Gluten Free?
Not automatically. Many boxes of Cheerios are labeled gluten free, but you should check the label on your box and your marshmallows before serving anyone with a gluten allergy.
Why This Recipe Works
The ratio does most of the work here. A full 10-ounce bag of marshmallows with only 1/4 cup of butter and 6 cups of Cheerios gives every ring a thin, even coat without leaving the bars wet or greasy.
Low heat protects the texture. Melting the marshmallows gently keeps them soft, and adding the vanilla and salt after the pot leaves the heat keeps the flavor fresh.
Folding the cereal gently and pressing it lightly leaves air between the rings, which is why the bars stay chewy instead of dense. Pressing just until level also means you can cut clean squares without the mixture crumbling.
Make Your Cheerio Bars Tonight
Cheerio bars are about as easy as a homemade treat gets, and the five-ingredient method means you can make them from pantry staples any night of the week. Grab a box of Cheerios and a bag of fresh marshmallows, and give this cheerio bars recipe a try.
When you make them, let us know how they turned out and which add-in you tried first.
