# Ingredient List:
→ Dry Ingredients
01 - 1 cup all-purpose flour
02 - 1/2 cup unsweetened cocoa powder
03 - 1/2 teaspoon baking powder
04 - 1/2 teaspoon salt
→ Wet Ingredients
05 - 1 cup unsalted butter, melted
06 - 1 1/2 cups granulated sugar
07 - 1/2 cup packed brown sugar
08 - 3 large eggs, at room temperature
09 - 2 teaspoons pure vanilla extract
→ Chocolate & Extras
10 - 3/4 cup semi-sweet chocolate chips or chunks
11 - 1/2 cup dark chocolate chips or chopped chocolate
12 - 2 cups mini marshmallows
# Step-by-Step Instructions:
01 - Preheat oven to 350°F. Grease and line a 9x13-inch baking pan with parchment paper.
02 - In a medium bowl, whisk together flour, cocoa powder, baking powder, and salt until well combined.
03 - In a large bowl, whisk melted butter, granulated sugar, and brown sugar until smooth.
04 - Add eggs one at a time to the wet mixture, beating well after each addition. Stir in vanilla extract.
05 - Gradually fold the dry ingredients into the wet mixture until just combined, avoiding overmixing.
06 - Fold in semi-sweet and dark chocolate chips or chunks evenly throughout the batter.
07 - Spread batter evenly in prepared pan and bake for 22 to 25 minutes.
08 - Remove pan from oven, scatter mini marshmallows over the surface, and gently press them into the batter.
09 - Return to oven and bake an additional 5 to 7 minutes until marshmallows are puffed and golden.
10 - Allow to cool completely in the pan before cutting into 12 squares for serving.
