6 tablespoons unsalted butter, plus more for pan

1 ½ cups semisweet chocolate chips (or 8 oz chopped bittersweet chocolate)

6 large egg yolks

6 large egg whites

½ cup granulated sugar

1. Preheat oven to 275 degrees.  Butter a 9-inch springform pan.
2. Place butter and chocolate in large bowl.  Microwave in 30-second increments, stirring each time, until melted; cool slightly.  Whisk in yolks.
3. In another bowl, beat egg whites to soft peaks.  Gradually add granulated sugar; beat until stiff and glossy.  Whisk ¼ of whites into chocolate mixture; gently fold mixture into remaining whites. 
4. Pour into prepared pan; smooth top.  Bake until cake pulls away from sides of pan and is just set in center, 45 to 50 minutes.  Cool completely on a wire rack.  Serve dusted with confectioners’ sugar, homemade whipped cream, and raspberry sauce.

Serves 8