Preheat oven to 350 degrees F. Grease and flour a 10-inch fluted tube pan; set aside.

In a small heavy saucepan, cook and stir 4 ounces white chocolate over low heat until melted. In a medium bowl, combine flour, the finely ground almonds, the baking powder, baking soda, and salt. Set aside.

In a very large bowl, beat butter with an electric mixer on medium to high speed for 30 seconds. Gradually add sugar, beating about 10 minutes or until mixture is fluffy and lighter in color. Add eggs one at a time, beating about 1 minute after each addition and scraping side of bowl frequently. Add vanilla, almond extract, and melted white chocolate; beat just until combined.

Alternately add flour mixture and sour cream to butter mixture, beating on low to medium speed after each addition just until combined. Do not overmix. Spread batter in the prepared pan.

Bake for 55 to 60 minutes or until a toothpick inserted near the center of the cake comes out clean. Cool cake in pan on a wire rack for 15 minutes. Remove cake from pan; cool completely on a wire rack.

For glaze: In a small heavy saucepan, combine 4 ounces white chocolate and the shortening. Cook and stir over low heat until melted. Spoon glaze over pound cake and sprinkle with the chopped almonds. Let stand until glaze is set. Makes 16 to 20 servings.