Monster Cookie Bars

Monster cookie bars are peanut butter oatmeal bars filled with chocolate chips and Reese's Pieces candies. They're great for potlucks and parties, especially Halloween!

Prep Time 15

Cook Time 25

Total Time 40

Servings bars

Author Heather

Ingredients

½ cup (113 g) unsalted butter melted
1 cup (270 g) creamy peanut butter
1 cup (213 g) brown sugar
½ cup (99 g) granulated sugar
2 large eggs room temperature
2 teaspoons vanilla extract
1 ½ cups (180 g) all-purpose flour *measured properly
½ teaspoon kosher salt
1 teaspoon baking soda
3 cups (267 g) old fashioned oats
1 cup (170 g) chocolate chips
1 cup (188 g) Reese's Pieces candies

Instructions

Preheat oven to 350℉. Line a 9x13 baking pan with parchment paper and set aside.
In a large bowl, add melted butter, brown sugar, and granulated sugar. Stir to combine. Add eggs and vanilla extract and stir until incorporated.
In a separate bowl, sift together the flour, salt, and baking soda. Gradually stir dry ingredients into butter mixture until just combined. Add oats, chocolate chips, and Reese's Pieces and stir until just combined.
Pour batter into 9x13 pan and use a spoon to spread evenly to the edges.
Bake for about 26 to 32 minutes, or until evenly browned across the top and set in the center. Use a toothpick in the center to check for doneness. Remove from oven and allow to cool before slicing and serving.

Notes

* How to measure flour properly: Use a kitchen scale to measure flour for accurate results every time. If you don't have a kitchen scale, use the spoon and level method. Stir the flour (especially if it's been packed down in a bag/container), then gently spoon into the measuring cup, leveling off the top with a knife. Scooping with a measuring cup compacts flour into the cup and adds up to 25% extra to the recipe, resulting in dry, bland bars.
Storage: Cookie bars will keep for 5-7 days in a sealed container. To help keep bars fresh, place a slice of bread in the container with the bars. Replace the bread slice as needed.
Freezing: Cookie bars freeze well, up to 3 months in a sealed plastic container or freezer bag.
Mix-ins: Chocolate chips and Reese's Pieces can be substituted with chopped nuts, M&M's candies, or other baking chips.

Nutrition