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Monster Oatmeal Chocolate Chip Cookie Bars

Monster Oatmeal Chocolate Chip Cookie Bars

Chewy, mix-in–loaded oatmeal cookie bars studded with semi-sweet chocolate chips and colorful Reese’s pieces for a sweet, slightly crunchy bite. Ready in about 30 minutes, these one-bowl, no-chill bars are ideal for Halloween treats, bake sales, or easy make-ahead snacks.
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Prep Time:10 minutes
Cook Time:20 minutes
Total Time:30 minutes
Course: Desserts
Keyword: cookie bars, fall, Halloween, no-chill, one-bowl

Equipment

  • 9x13-inch baking dish
  • large mixing bowl or stand mixer

Ingredients

  • 2 1/2 cups old fashioned oats
  • 2 cups all-purpose flour
  • 1 cup brown sugar packed
  • 1/2 cup granulated sugar
  • 1 teaspoon baking soda
  • 1 teaspoon salt
  • 1 cup canola oil
  • 2 large eggs
  • 1 tablespoon vanilla extract
  • 1 1/2 cups semi-sweet chocolate chips
  • 1/2 cup Reese’s pieces or M&M’s

Instructions

  1. Preheat the oven to 350 degrees F. Grease a 9×13 inch baking dish with butter or line it with parchment paper.
  2. In a large mixing bowl or the bowl of a stand mixer, combine the old fashioned oats, all-purpose flour, brown sugar, granulated sugar, baking soda, salt, canola oil, eggs, and vanilla. Beat until the dough is moist and all ingredients are combined; the dough will be crumbly.
  3. Stir in the semi-sweet chocolate chips and 1/4 cup of the candy pieces. Press the dough evenly into the prepared baking dish, then scatter the remaining 1/4 cup candy pieces over the top. Bake 18-20 minutes or until the edges are set and the bars are golden. Let cool completely, then cut into bars.

Notes

1. The dough will be crumbly but holds together when pressed into the pan—press firmly for even bars. 2. The recipe divides the 1/2 cup candy into 1/4 cup mixed into the dough and 1/4 cup for topping so you get candy throughout and a festive top. 3. This is a no-chill, one-bowl recipe—bake immediately after mixing.