- 1 1/2 cups all-purpose flour
- 1/2 teaspoon baking soda
- 1 teaspoon baking powder
- 1/2 teaspoon cornstarch
- 1/4 teaspoon salt
- 1/2 cup room temperature butter
- 1/2 cup white sugar
- 1/4 cup firmly packed brown sugar
- 1 large egg room temperature
- 1 1/2 teaspoons pure vanilla extract
- 1 1/4 cup white chocolate chips separated
- 3 cups miniature marshmallows
- 3/4 cup pastel M&Ms or other candy
- 1/2 cup broken pretzel twists
- 3 tablespoons sprinkles pastel colored
- Preheat oven to 350 degrees F. Spray 9×13 inch pan with non-stick spray or line with parchment paper.
- In a medium bowl, add the flour, baking soda, baking powder, cornstarch, and salt. Stir to combine. Set aside.
- Mix room temperature butter and sugar together with mixer until light and fluffy. Now, mix in the egg and vanilla and beat until just incorporated.
- Slowly add the dry ingredients to the wet ingredients and mix until combined. Add one cup of white chocolate chips to mixture and stir with spatula.
- Press cookie dough into prepared pan. Bake cookie dough for 17-22 minutes or until edges are slightly browned and middle is starting to set. Remove from oven and immediately top with marshmallows. Return to the oven and another 1-2 minutes or until marshmallows become puffy.
- Take out of the oven and let sit for 1-2 minutes to cool slightly. Add the M&M and other festive candy as well as the 1/4 cup of white chocolate chips, broken pretzels, and pretty sprinkles.
- Let cool completely and then cut into squares. Enjoy!