Sour Cream and Chocolate Pound Cake

Heat oven to 325°.

Make liner from lightweight brown paper bag for 9 x 5" loaf pan. Combine flour, baking powder and salt in dry food processor container fitted with metal blade; process with 2 five-second on/off turns. Transfer to waxed paper.

Process chocolate in food processor container fitted with metal blade until chocolate forms beads, about 13 seconds. Add eggs; process 15 seconds. Process, adding butter in thin stream within 15 seconds; process 20 seconds. Scrape down side of container. Process, gradually adding sugar within 12 seconds; process 20 seconds. Add sour cream and vanilla; process with 5 half-second on/off turns. Scrape down side of container.

Add half the flour mixture to egg mixture; process with 4 half-second on/off turns. Scrape down side of container. Add remaining flour mixture; process with 5 or 6 half-second on/off turns just until flour is mixed into batter.

Pour batter into prepared pan. Bake on center oven rack until wooden pick inserted in center is withdrawn clean, about 1 hour 25 minutes. Cool cake in pan on wire rack 15 minutes. Remove cake from pan; cool in paper liner to room temperature. Refrigerate in liner wrapped in plastic wrap overnight before serving.