Recipe Summary

Preparation time: 45 minutes
Number of servings: 16 (2x2 inch piece)

Ingredients

6 ounces semisweet chocolate
1/2 cup hot water
4 egg whites
1 teaspoon vanilla extract
2/3 cup granulated sugar
1-1/2 cups all-purpose flour
1 teaspoon baking powder
1/2 cup chopped walnuts

Directions

Preheat the oven to 350°F. Spray an 8x8-inch cake pan with nonstick cooking spray. In a large heatproof bowl set over simmering water, melt the chocolate with the hot water, stirring until smooth.

Source: National Institute of Health, National Heart, Lung, and Blood Institute