Rocky Road Brownies

Steps

1. Line the bottom and sides of an 8-inch-square baking pan with parchment paper or foil coated with cooking spray.

2. Thoroughly whisk flour, baking powder and salt in a small bowl.

3. Melt butter in a medium saucepan until sizzling. Remove from the heat and stir in cocoa, then sugar. (The mixture will look like a mass of very dark brown sugar.) Add egg, egg whites and vanilla. Stir briskly until smooth and glossy. Stir in the flour mixture until just incorporated. Then stir briskly for about 50 strokes. Scrape the batter into the prepared pan and spread it evenly. The batter will be very shallow in the pan. If you have time, cover the pan and refrigerate for a few hours or up to 12 hours. (This hydrates the cocoa powder and flour and brings all the flavors into sharper focus.) Remove from the refrigerator about 30 minutes before baking; preheat oven to 350°F.

4. Quarter marshmallows with an oiled knife. Distribute the pieces over the batter, pressing them in. Sprinkle chips over the top.

5. Bake the brownies until the marshmallows are golden brown, 25 to 35 minutes. Let cool completely in the pan on a wire rack for about 2 hours. Cut into 16 brownies (190 calories each).