6 tablespoons unsalted butter
11 ounces best-quality semi-sweet chocolate, coarsely chopped
3 large eggs
1 cup sugar
3/4 cup all-purpose flour
1/4 cup unsweetened cocoa
1/8 teaspoon baking soda
1 cup coarsely chopped walnuts (optional)
Nonstick cooking spray
Chocolate frosting if desired
1. Preheat the oven to 350°. Line a twelve-count muffin tin with cupcake liners, and spray generously with nonstick cooking spray. Set aside.
2. In a saucepan over low heat, melt the butter and 8 ounces of chocolate. Stir until smooth. Remove from heat, and set aside.
3. In a large bowl, whisk together eggs and sugar. Add flour, cocoa, and baking soda. Stir in the melted chocolate until combined. Stir in remaining 3 ounces of chocolate and nuts if desired.
4. Using a 2-ounce ice cream scoop, fill cupcake liners 3/4 full with batter. Bake until a firm crust forms on the cupcakes, about 20 minutes. Remove to a wire rack to cool, about 10 minutes. Remove cupcakes from pan, and continue to cool on a wire rack.
5. Ice cupcakes with a generous amount of chocolate frosting.