These Lucky Charms Cookie Dough Bars are a magically delicious dessert consisting of three layers: a sweet and buttery cereal crust, a marshmallow packed cookie dough middle, and a simple buttercream frosting top.

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My favorite thing is when I post something on my blog and my mom calls me and says, "ooh your dinner looked so good tonight!" And I'm like, "that was my dinner 2 months ago." Because typically, it takes me at least a month from the time I make a recipe until the time I post it on my blog.
In addition to testing the recipe multiple times, doing a photo shoot, editing the photos, and writing the post, bringing my content live takes a lot of hours. And I have a lot of recipes in progress at all times (I currently have at least 5 new recipes that are finished and ready to post and about 20 recipe photo updates).
But these Lucky Charms Cookie Dough Bars? I made these bars on Monday and am posting them today. They are so freaking delicious and St. Patrick's Day is coming up quickly and I just couldn't wait another minute.
So, if my mom calls me tonight and says "your dessert tonight looked delicious!" I'll say, "thank you, it was!"
❓ Is raw cookie dough safe to eat?
First things first, if you're new here, you may not know about all the cookie dough treats I post. Clearly, I'm all about eating raw cookie dough, but there are a few things you need to do to make it safe to eat.
Probably the most obvious? Don't include eggs in your cookie dough. None of my raw cookie dough recipes involve eggs, so you're good to go there.
The not so obvious? Bake your flour. Many people think it's the eggs in raw cookie dough that causes illness, but it's often actually the raw flour that causes foodborne illness (source).
The solution? Bake your flour before adding it to the cookie dough. You can easily do this by spreading flour on a cookie sheet and baking it at 350 degrees for just five minutes.
Because of this, I guess these cookie dough bars can't technically be considered "no bake," but since you don't have to bake the bars, I'm still referring to them that way.
Plus, you can always buy heat-treated flour so you can skip the baking step. Also, I'll admit I've made cookie dough many times without baking the flour. But especially if you're serving these to kids, the elderly, or people with compromised immune systems, I recommend baking it!
❤️ Why you'll love this recipe
All of my cookie dough bar recipes are super easy to make and consist of a crust, a cookie dough middle, and some sort of topping. And they're fabulous!
For these Lucky Charms cookie dough bars, I used the cereal (sans marshmallows) as a crust, a Lucky Charms marshmallow cookie dough middle, and a simple buttercream icing top.
These are the perfect any time of year treats for all Lucky Charms fans. But they're especially fun during St. Patrick's Day season.
🗒 Ingredients
Despite having three layers, the ingredients for these Lucky Charms bars are pretty simple. Here's everything you need (be sure to view the recipe card at the bottom of this post for ingredient amounts and full recipe instructions):
For bottom layer:
- Toasted oats from Lucky Charms cereal (no marshmallows)
- Granulated sugar
- Melted unsalted butter
For middle layer:
- Unsalted butter
- Granulated sugar
- Vanilla extract
- Salt
- Lucky Charms marshmallows
- All-purpose flour: be sure to see notes on heat-treating
- Whole milk
For top layer:
- Unsalted butter
- Confectioners' sugar
- Vanilla extract
- Salt
- Lucky Charms marshmallows
If you don't feel like picking all the marshmallows out of your Lucky Charms, you can purchase an entire bag of just marshmallows (they're great for snacking, too!).
🥣 How to make cereal crust
Every time I make cookie dough bars (which is probably admittedly too often), I use Oreo cookie crumbs for the crust. When I make cheesecake bars, I often use gingersnaps, graham crackers, or Nilla Wafers. But what if... I thought to myself.. I used plain old cereal instead?
I figured it was worth a try so I added just the toasted oats part of the Lucky Charms to a food processor, along with some granulated sugar. I processed until the cereal was fine crumbs and then I added in melted butter and pulsed a few more times to form a crust.
Then I poured it into a foil-lined 8x8 baking pan lightly sprayed with cooking oil and pressed it down and popped it in the freezer for 30 minutes.
Easy and delicious!
👩🍳 How to make cookie dough filling
The cookie dough filling is just a simple edible cookie dough with vanilla and Lucky Charms marshmallows mixed in.
Start by beating butter and sugar on medium speed in the bowl of a stand mixer (or in a large bowl with a hand mixer), until light and fluff, 3-4 minutes. Then beat in vanilla and salt and stir in Lucky Charms marshmallow pieces.
With mixer on low, slowly add flour to bowl until well combined. Add milk until the dough comes together.
Press the cookie dough into a smooth layer over the chilled crust.
Now, you just have one more step to go.
🧁 How to make buttercream frosting
This part is easy, too! I often like to top my cookie dough bars with just a thin layer of buttercream frosting because it looks nice and adds some more sweetness (not that these necessarily need any more sweetness, but I'll always take it!).
My buttercream frosting is just room temperature butter, confectioners' sugar, and vanilla.
I spread the buttercream frosting over the cookie dough and topped with remaining marshmallows.
Then popped the whole shebang in the fridge for 45 minutes so chill and make slicing easier.
You can either slice these into large bars (and get about 16) or smaller bars (and get about 36). I liked the large bar look, but these are so sweet and indulgent that I recommend small.
Plus, that means you'll have more to share... And you can always have 2 if you want!
These Lucky Charms cookie dough bars taste just like a bowl of Lucky Charms. But a bowl of Lucky Charms that melts in your mouth and is even more delicious than you could possibly imagine.
I'm so happy I was able to utilize the toasted oats boring part of Lucky Charms cereal to these bars. I think it really helped make these bars as delicious as they are and I was also very pleased with how the crust held together.
I still had lots of toasted oat cereal leftover from the box and utilized all the marshmallows, so maybe I'll have to buy a big bag of Lucky Charms marshmallows to make some more of these Lucky Charms desserts without wasting any cereal.
⏲️ How to store
These Lucky Charms cookie dough bars are easy to store (if you don't eat them all right away!).
I recommend keeping the sliced bars in an airtight container in the fridge. You can store them at room temperature for a couple days if your kitchen isn't too warm, but they will keep for about a week in the fridge and actually taste even better chilled!
Chris also loves them when frozen. They'll keep fresh best if you wrap them individually in plastic wrap before freezing, but you can put in the freezer in an airtight container if you're planning to eat them within a couple weeks.
🌈 More Lucky Charms desserts
If you're as obsessed with the sugary cereal as I am, you'll want to use it in all your dessert recipes! Here are some of my favorite treats featuring the cereal:
- Granola Bars
- Oatmeal
- Hot Chocolate
- Ice Cream
- Doughnuts
- Martini
- Ice Box Pie (from The Slow Roasted Italian)
- Ice Cream Sandwiches (from Simply Whisked)
Chris always says he knows one of my recipes is really good when I say multiple times, "This is so good!!" because I guess I apparently don't talk up many of the things I make (even when I do think they're super delicious!). But he's right...
And I think I've eaten more of these Lucky Charms cookie dough bars than I have any dessert I've made in recent times (these molasses ginger cookies are the closest contenders).
🍪 More cookie dough recipes
I'm also obsessed with all things cookie dough and have lots of edible cookie dough recipes for you! Be sure to check them all out:
See more Cookie Dough Recipes →
If you're going to any St. Patrick's Day parties or just need a fun to dessert to celebrate one of America's most loved cereals, I hope you'll make these Lucky Charms cookie dough bars!
📖 Recipe
Lucky Charms Cookie Dough Bars
Ingredients
Cereal Crust
- 3 cups toasted oats from Lucky Charms (no marshmallows)
- ¼ cup granulated sugar
- ½ cup (1 stick) unsalted butter, melted
Lucky Charms Cookie Dough
- ¾ cups ( 1 ½ sticks) unsalted butter, room temperature
- 1 cup granulated sugar
- 2 tablespoon vanilla
- ¼ teaspoon salt
- 1 ½ cups Lucky Charms marshmallows
- 2 cups all-purpose flour (see note about baking)
- 5 tablespoon whole milk
Buttercream Frosting
- 4 tablespoon unsalted butter, room temperature
- 1 cup confectioners' sugar
- 2 teaspoon vanilla
- ⅛ teaspoon salt
- ½-3/4 cup Lucky Charms marshmallows
Instructions
Cereal Crust
- Put toasted oats cereal and sugar in a food processor and blend until it turns into fine crumbs. Pour in melted butter and pulse a few times until well blended.
- Line an 8x8 baking pan with foil and lightly coat with cooking spray. Pour cereal crumbs into baking pan and press down into even layer on bottom of pan.
- Place pan in freezer for 30 minutes while you prepare the cookie dough.
Lucky Charms Cookie Dough and Assembly
- In the bowl of a mixer or in a large bowl with a hand mixer, cream butter and sugar on medium speed until light and fluffy, 3-4 minutes.
- Add vanilla and salt and blend until combined. Stir in Lucky Charms marshmallows.
- With mixer on low, slowly add flour to bowl until well combined. Keep mixer on low and add milk in until dough comes together.
- Remove pan with cereal crust from freezer and press cookie dough into an even layer over crust.
- Spread buttercream frosting over the top of the cookie dough and smooth evenly with a spatula. Press additional marshmallows onto the top of the frosting.
- Place pan in fridge chill for at least 45 minutes. Once chilled, remove bars from pan by lifting foil. Using a sharp knife, slice into squares. You can cut large squares and get about 16 or small squares and get about 36.
Buttercream Frosting
- In the bowl of an electric mixer or in a large bowl with a hand mixer or whisk, beat together butter and confectioners's sugar.
- Mix in vanilla extract and salt. You can add food coloring if you want to make the frosting a fun color, but I kept mine white.
Notes
- To ensure flour is safe for eating (raw flour can cause foodborne illness), you can toast it. Just spread flour on a baking sheet and bake at 350 degrees for about 5 minutes.
- I recommend keeping these bars in the fridge in an airtight container.
Gemma says
Oh my gosh I can only imagine how delicious these are! I love how gooey Lucky Charms are, so to use them in a cookie dough bar is my idea of heaven! xo