Chocolate Quatre-Quarts

3 ounces semisweet or bittersweet chocolate, melted in a double boiler or for 2 minutes in a microwave oven
½ cup all-purpose flour
½ cup cake flour
¼ teaspoon baking soda
Large pinch kosher salt
3 large eggs, room temperature, separated
1 cup unsalted butter, room temperature, plus small amount for the pan
¾ cup granulated sugar

Nutritional Information
- Nutritional analysis per serving (12 servings)
  275 calories; 18 grams fat; 11 grams saturated fat; 0 grams trans fat; 5 grams monounsaturated fat; 0 grams polyunsaturated fat; 25 grams carbohydrates; 0 grams dietary fiber; 16 grams sugars; 3 grams protein; 87 milligrams cholesterol; 71 milligrams sodium

12 servings

Position rack in lower third of oven. Preheat oven to 375 degrees. Butter an 8 1/2-by-4 1/2-by-2 1/2-inch loaf pan.
Melt chocolate and set aside.
Sift together flours, soda and salt. Set aside.
Place egg whites in the bowl of an electric mixer. Beat on medium-high speed until stiff but not dry. Scrape whites into another bowl and set aside.
Place butter in the mixer bowl and beat on medium-high speed until creamy. Gradually add sugar. Beat until very light and fluffy, stopping occasionally to scrape sides of bowl.
Add egg yolks and beat until fluffy, stopping once to scrape down sides of bowl. Add dry ingredients and beat just until mixed. Beat in chocolate.
Remove bowl from mixer. Stir about one third of the egg whites into the batter. Fold in remaining whites. Scrape batter into prepared pan. Bake for 1 hour 20 minutes, rotating pan after 40 minutes.
Let cool in pan for 10 minutes. Turn cake out onto rack, turn upright and cool completely.
Wrap cake tightly in plastic wrap and then aluminum foil. Refrigerate overnight or up to a week. Can be frozen for up to two months. (Defrost in refrigerator overnight.)

2 hours