Looking for a festive bake that’s easy to make but just screams Christmas? This is it! These Santa cookie bars are a deceptively simple but totally over-the-top dessert that I think you’ll want to make every year from now on. We’ve got a buttery cookie base, melty chocolate chips, colorful M&M’s, and a hidden layer of Oreos baked right in the middle (I recommend going for the Christmas ones with the red layer inside for extra festivity, but the standard ones work just fine too if that’s all you can get hold of).

They’re soft, chewy, a little bit retro, and just so wonderfully Christmassy. The best part is that you mix everything in one bowl, press it into a pan, and bake. No scooping, no chilling, no multiple trays. Just big, thick cookie bars that slice beautifully and taste even better the next day (if they last that long)!

Don’t miss my other favorite Christmas bakes! I think you’ll also enjoy my Christmas tree cupcakes, cake batter Christmas cookies, cranberry and orange Christmas tree pies, chocolate chip reindeer muffins, reindeer brownie bites, and Santa hat cupcakes!

Ingredients

Please note that you’ll find a printable recipe card at the bottom of this post!

Unsalted butter – softened to room temp so it creams perfectly with the sugar.
Brown sugar – adds moisture and a deep, caramel-like sweetness.
Granulated sugar – for that classic cookie texture and balanced sweetness.
Eggs – bind everything together and keep the bars soft.
Vanilla extract – adds that warm, cozy cookie flavor.
All-purpose flour – gives the bars structure while keeping them soft and chewy.
Salt – just a pinch to balance all the sweetness.
Mini chocolate chips – for melty pockets of chocolate in every bite.
Crushed Christmas Oreos – the secret to extra crunch and holiday magic (plus 9 whole Oreos for layering in the middle).
Christmas M&M’s – colorful, festive, and perfectly melty on top.

How To Make Santa’s Cookie Bars

Preheat your oven to 350°F and line an 8×8-inch baking pan with parchment paper, leaving a little overhang on the sides to lift the bars out later.
In a large mixing bowl, cream together the butter, brown sugar, and granulated sugar until light and fluffy — about 2–3 minutes.
Beat in the eggs, vanilla extract, and salt until smooth and well combined.
Add the flour and mix until just combined — don’t overmix or the bars can turn dense.

Fold in the chocolate chips, M&M’s, and crushed Oreos, saving a handful of each for the top.

Press about ⅓ of the cookie dough evenly into the bottom of your prepared pan.
Arrange the 9 whole Oreos in a single layer across the dough.

Gently spread the remaining cookie dough on top, pressing it out evenly to cover the Oreos.
Sprinkle the reserved crushed Oreos and M&M’s over the top for that festive look.

Bake for 22–25 minutes, or until the top is golden brown and a toothpick inserted in the center comes out mostly clean (a few crumbs are fine!).
Let the bars cool in the pan for about 10–15 minutes before lifting them out and slicing.

Storage

Store your Santa’s cookie bars in an airtight container at room temperature for up to 3 days or in the fridge for up to 5 days. If you like them extra gooey, pop a bar in the microwave for 10–15 seconds before serving.

You can also freeze them for up to 3 months. Just wrap each bar individually in plastic wrap, then store in a freezer-safe bag or container.

Recipe Notes

Make sure your butter is softened, not melted. It should be easy to press with your finger but still hold its shape. That’s how you get that perfect soft-and-chewy texture.
Don’t overmix once you add the flour. Just stir until it’s combined. Overmixing can make the bars tough.
When layering the Oreos, press them gently into the bottom dough so they stay centered once you add the top layer.
These bars are done when the edges are golden and the center looks set but still soft. They’ll continue to firm up as they cool.
For clean slices, cool completely before cutting. Or if you can’t wait (understandable), chill for 20 minutes first to make it easier.
Use the parchment overhang to lift the bars out of the pan. It’s a total game changer for neat squares.

Variations

White Chocolate Peppermint Bars: Swap the chocolate chips for white chocolate chips and add a handful of crushed candy canes for a peppermint twist.
Peanut Butter Christmas Bars: Replace half of the butter with creamy peanut butter and use peanut butter M&M’s for an extra-rich version.
Salted Caramel Cookie Bars: Drizzle caramel sauce over the Oreo layer before adding the top cookie dough, then finish with a sprinkle of flaky sea salt.
Grinch Bars: Use green M&M’s and Golden Oreos instead of chocolate ones. Cute, fun, and perfect for kids!
New Year’s Version: Swap the red and green M&M’s for gold and silver sprinkles. Same recipe, new holiday vibe.

Serving Ideas

Cut these into big squares for parties or smaller bite-sized pieces for cookie platters and bake sales. They make great edible gifts, too. Just wrap a few in clear treat bags, tie with a red ribbon, and add a festive tag. (Santa would definitely approve!)

At home, serve them slightly warm with a glass of milk or a mug of hot cocoa for the ultimate cozy moment. Or turn them into a dessert plate showstopper — top a warm square with a scoop of vanilla ice cream and a drizzle of chocolate or caramel sauce!

Print Recipe

Santa's Cookie Bars

These Santa’s cookie bars are soft, chewy, and loaded with all the festive favorites — chocolate chips, Christmas M&M’s, and crushed Oreos with a surprise layer of whole cookies in the middle. They’re rich, buttery, and completely irresistible, making them perfect for holiday parties, cookie trays, or cozy nights in with a mug of cocoa. One bite, and you’ll see why Santa would definitely approve!

Prep Time10

Cook Time25

Total Time35

Course: Dessert

Servings:

Ingredients

1 cup unsalted butter softened
½ cup brown sugar
½ cup granulated sugar
2 large eggs
1 tsp vanilla extract
2 cups all-purpose flour
¼ tsp salt
¾ cup mini chocolate chips
1 cup crushed Christmas Oreos plus 9 whole Oreos for layering
¼ cup Christmas M&M’s

Instructions

Preheat your oven to 350°F and line an 8x8-inch baking pan with parchment paper, leaving a little overhang on the sides to lift the bars out later.
In a large mixing bowl, cream together the butter, brown sugar, and granulated sugar until light and fluffy — about 2–3 minutes.
Beat in the eggs, vanilla extract, and salt until smooth and well combined.
Add the flour and mix until just combined — don’t overmix or the bars can turn dense.
Fold in the chocolate chips, M&M’s, and crushed Oreos, saving a handful of each for the top.
Press about ⅓ of the cookie dough evenly into the bottom of your prepared pan.
Arrange the 9 whole Oreos in a single layer across the dough.
Gently spread the remaining cookie dough on top, pressing it out evenly to cover the Oreos.
Sprinkle the reserved crushed Oreos and M&M’s over the top for that festive look.
Bake for 22–25 minutes, or until the top is golden brown and a toothpick inserted in the center comes out mostly clean (a few crumbs are fine!).
Let the bars cool in the pan for about 10–15 minutes before lifting them out and slicing.

These cookie bars really do just look, feel, and taste like Christmas, and I hope you’ll have just as much fun making them as I did! These look fantastic in photos, so if you take any, I’d love to see them. You can tag me on Instagram @slimmingviolet, and of course you can share your thoughts and comments below. I read every single one, and it helps me to create more recipes you’ll love. Happy baking, and happy holidays!