Monster Cookie Bars
Thick, chewy monster cookie bars loaded with peanut butter, oats, chocolate chips, peanut butter chips and M&Ms, baked in one 9x13 pan.
Ingredients
- 3/4 cup unsalted butter, softened
- 1 cup packed brown sugar
- 1/2 cup granulated sugar
- 3/4 cup creamy peanut butter (not natural)
- 1 large egg plus 1 egg yolk
- 1 teaspoon vanilla extract
- 1 1/2 cups all-purpose flour
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 1 1/2 cups old-fashioned oats
- 1 cup peanut butter chips
- 3/4 cup semi-sweet chocolate chips
- 3/4 cup M&Ms, plus extra for the top
Instructions
- Preheat the oven to 350°F. Grease a 9x13-inch pan or line with parchment paper, leaving an overhang on two sides.
- Beat the butter, brown sugar, granulated sugar and peanut butter on medium speed until light and fluffy, about 2 minutes.
- Beat in the egg, egg yolk and vanilla until smooth.
- Add the flour, baking soda and salt and mix on low just until combined. Stir in the oats.
- Fold in the peanut butter chips, chocolate chips and M&Ms, saving a small handful of each for the top.
- Press the dough evenly into the pan. Scatter the reserved mix-ins on top and press lightly.
- Bake 20–22 minutes, until the edges are golden and the center looks just set. Do not overbake.
- Press a few extra M&Ms into the warm top if desired. Cool completely in the pan, at least 1 hour, then lift out and cut into bars.
Notes
Pull the bars when the center still looks slightly soft; they finish setting as they cool.
Use regular creamy peanut butter. Natural peanut butter makes the bars greasy and crumbly.
Store airtight at room temperature up to 4 days, or freeze individually wrapped up to 3 months.
Use regular creamy peanut butter. Natural peanut butter makes the bars greasy and crumbly.
Store airtight at room temperature up to 4 days, or freeze individually wrapped up to 3 months.