Halloween Reese’s Monster Cookie Bars

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Get in the spirit of this spooky season with these adorable Flourless Halloween Reese’s Monster Cookie Bars! These are like monster cookies only in bar form with a delicious chocolate peanut butter topping and Reese’s Ghosts for a ghostly effect!  Gluten free and delish!

More Halloween delights?  Check out Best Monster Cookies, Flourless Peanut Butter Monster Cookies, Easy Halloween Cereal Treats and these Monster Nutella & Peanut Butter Cookies!

History of Monster Cookies

Have you heard of Monster Cookies?  They’ve been around for quite along time, but it looks like the original recipe didn’t have flour either here (because he ran out!) and so the recipe became a cross between a peanut butter and oatmeal cookie with goodies, thus Monster Cookies.

(Perfect accident right?) These are like those, but we transformed cookies into a gluten free cookie bar for more party fun! Woohoo!

There’s no better treat than a homemade dessert, especially when there are zero grains or gluten involved, if you switch out the rolled oats for gluten-free oats!

That’s why this Halloween you should be making flourless Reese’s Cookie Bars – they are easy to make, don’t require flour, and are an absolute blast to enjoy with friends and family this Halloween season.

Why We Love These Fun and Flourless Halloween Reese’s Cookie Bars

• It’s Halloween season, and it’s time to get creative with your spooky treats!
• Easy to Make! The oatmeal cookie layer that’s made with no flour and butter!  Just press it into a pan and just bake. 
• Add peanut m&ms, raisins, nuts or coconut for some texture in your cookie bars if you want some more yumminess!
• The topping is just chocolate chips melted after they’ve cooled and adding the rest of the accessories.  Feel free to add a heaping tablespoon of peanut butter to the melted chocolate to make it a chocolate peanut butter layer, if you wish! 
• Those white chocolate covered ghosts are peanut butter cups in the shape of scary ghosts from Reese’s (I rather think cute, not scary).  With that being said, we know they are excellent party favors to snack on all alone.  *Note to self* Buy 2 bags. 
• These monster cookie bars are perfect when you want gluten free treats for Halloween, just by switching out the oats for gluten free oats!
• Perfect sweet treats for Halloween and fall fun for the kids and adults!

Ingredients You Need  

• peanut butter
• brown sugar 
• vanilla
• eggs
• old-fashioned rolled oats or gluten free oats, if wanting gluten free option
• baking soda
• salt
• semisweet chocolate chips
• Reese’s Halloween White Snack Size Ghosts
• Reese’s Piece’s Candies
• Eyeballs
• Sprinkles

How to Make the Monster Cookie Bars 

1. Preheat oven to 350°F. Line a 9 x 13-inch baking dish with parchment paper and spray with non-stick cooking spray. Set aside.
2. Using a mixer, beat the peanut butter and brown sugar together until smooth. Add the vanilla and then the eggs, one at a time until well mixed.
3. Add the oats, baking soda and salt and mix until just combined.
4. Press dough evenly into prepared baking dish. Bake for 30 minutes or until the top of the bars starts to turn golden brown.
5. Remove from oven and let cool.

Microwaving Chocolate Chips for A Luscious Chocolate Layer On Top

1. Once bars have cooled, microwave chocolate chips in 30 second increments up 2 2 minutes and then pour and spread on top of the bars. Feel free to add a heaping tablespoon of peanut butter to the melted chocolate to make it a chocolate peanut butter layer, if you wish! 

Decorating the Tops of the Halloween Monster Cookie Bars

1. Unwrap the ghosts and place them on top of the chocolate and sprinkle the sprinkles on top of the melted chocolate. If you have eyeballs, randomly place those on top of the chocolate.
2. To place the eyeballs on the ghosts, melt some white chocolate chips and dip the back of a spoon in the chocolate, then place the back of the eyeball on the back of the spoon to get some chocolate so it’s like glue. Place it on the ghost.
3. Let chocolate set before cutting. Place in fridge for 15 minutes for faster devouring needs.

Whether you’re hosting a haunted house party, going to a fright fest, or need a quick Halloween treat for the kiddies, these are really fun and festive! Also, great for those avoiding flour and wanting gluten-free treats!

For More Halloween Ideas, Check These OUT!

• BUTTERFINGER® Peanut Butter Cup Skulls Tombstone Treats
• Halloween Peanut Butter Rice Krispie Ghosts
• Cream Filled ‘Ghosts In the Graveyard’ Cupcakes
• 10 Halloween Party Desserts & Jello Shots!
• Halloween Skull Cupcakes
• 20 Spooktacular Halloween Desserts Round-Up!
• Monster and Mummy Chocolate Covered Graham Cracker Cookies
• Halloween Cake Mix Cookies
• Soft Batch Monster Cookies

Flourless Halloween Reese's Cookie Bars

Kim Lange

Get in the spirit of this spooky season with these adorable Flourless Halloween Reese's Cookie Bars! These are like monster cookies only in bar form with a delicious chocolate peanut butter topping and Reese's Ghosts for a ghostly effect!  

5 from 7 votes

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 30 minutes mins

Course Dessert

Servings 15 Servings

Calories

Ingredients

  

1x2x3x

• 2 cups peanut butter
• 1 cup brown sugar packed
• 1 teaspoon vanilla
• 2 large eggs
• 2-1/2 cups old-fashioned rolled oats gluten free oats if wanting gluten free option
• 1 teaspoon baking soda
• 1 teaspoon salt
• 2 cups semisweet chocolate chips Feel free to add a heaping tablespoon of peanut butter to the melted chocolate to make it a chocolate peanut butter layer, if you wish! 
• 1 10.2 oz bag Reese's Halloween White Snack Size Ghosts
• Reese's Piece's Candies
• Eyeballs
• Sprinkles

Instructions

 

• Preheat oven to 350°F. Line a 9 x 13-inch baking dish with parchment paper and spray with non-stick cooking spray. Set aside.
• Using a mixer, beat the peanut butter and brown sugar together until smooth. Add the vanilla and then the eggs, one at a time until well mixed.
• Add the oats, baking soda and salt and mix until just combined.
• Press dough evenly into prepared baking dish. Bake for 30 minutes or until the top of the bars starts to turn golden brown.
• Remove from oven and let cool.
• Once bars have cooled, microwave chocolate chips in 30 second increments up to 2 minutes and then pour and spread on top of the bars.
• Unwrap the ghosts and place them on top of the chocolate and sprinkle the sprinkles on top of the melted chocolate. If you have eyeballs, randomly place those on top of the chocolate.
• To place the eyeballs on the ghosts, melt some white chocolate chips and dip the back of a spoon in the chocolate, then place the back of the eyeball on the back of the spoon to get some chocolate so it’s like glue. Place it on the ghost.
• Let chocolate set before cutting. Place in fridge for 15 minutes for faster devouring needs.

Keyword bars, flourless, halloween, monster cookies, oatmeal bars, oats, party treats

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