Preheat oven to 350 degrees. Spray or grease 12 muffin cups.
In a medium sized microwave-safe bowl combine sugar, softened butter, and water. Microwave on high for about 45 seconds or until butter is melted. Stir in 3/4 cup semi-sweet chocolate chips until melted. Stir in egg and vanilla extract, mix well. Add flour and baking soda, stir until combined. Allow the batter to cool to room temperature (doesn't take very long). Then, stir in 3/4 cup milk chocolate chips and remaining 1/4 cup of semi-sweet chocolate chips. Spoon batter evenly into muffin cups.
Bake for 13-15 minutes or until top is set and a toothpick inserted into center comes out slightly wet. After brownies are out of the oven, wait for centers to fall. This will happen upon cooling. If not (they did not for me) then tap the centers with the back of a teaspoon to make a hole for the peanut butter.
Place peanut butter in a small microwave-safe bowl. Microwave on high for 45 seconds then stir. While brownies are still war spoon about a tablespoon full of peanut butter into the center of each brownie. Top with remaining 1/3 cup of milk chocolate and semi-sweet chocolate chips. Cool completely in pan.
Store at room temperature or in the refrigerator. To reheat the brownies just pop 'em in the microwave for 10-15 seconds. Liz, the official taste tester, and I found that we liked the brownies when they were warm and when they were cooled in the fridge for a little bit. So try both, it's an excuse to eat two, enjoy!
Reviews
☆☆☆☆☆
*Healthy Swaps: I used egg whites instead of an egg (2 egg whites per egg called for) and reduced fat creamy peanut butter.
[I posted this recipe.]
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