Ice cold and creamy-smooth, this frozen dessert manages to be both rich and refreshing. If you’re not into the chocolate-cherry combination, substitute mini chocolate chips for the cherries.
1. Line 9- x 5-inch loaf pan with nonstick foil, allowing it to hang over sides of pan.
2. Fill saucepan with 2 inches of water, and simmer gently on medium heat. Whisk egg yolks and 3 Tbs. sugar in metal bowl placed over simmering water 4 minutes, or until mixture reaches 140°F on instant-read thermometer and becomes an opaque pale yellow custard that coats back of spoon. Transfer to large bowl, and set aside.
3. Wipe out metal bowl, and melt chocolate in it over simmering water. Fold chocolate into custard, then whisk in cocoa powder and cayenne pepper, if using. Whisk in yogurt, and set aside.
4. Rinse and wipe out metal bowl; place egg whites and remaining 1/2 cup sugar in bowl over saucepan of gently simmering water. Whisk 4 minutes, or until egg whites reach 140°F on instant-read thermometer and sugar dissolves completely. Beat egg whites with electric mixer 6 minutes, or until peaks form. Fold egg whites into chocolate custard. Fold in frozen cherries and pistachios. Transfer to prepared loaf pan, wrap in foil, and freeze 6 hours, or overnight.
5. Unmold onto cutting board, and cut into slices, dipping knife in warm water and wiping knife between each slice.