Grease the bottom and sides of a 9-in. round baking pan with 1 teaspoon butter. Sprinkle with confectioners' sugar; set aside. Place the almonds and sugar in a blender or food processor; cover and process until finely ground., In a small bowl, cream remaining butter; beat in almond mixture until combined. Add eggs, one at a time, beating well after each addition. Stir in sour cream and lemon zest. Combine the flour and baking powder; add to creamed mixture alternately with lemon juice., Pour into prepared pan. , Bake at 350degrees for 40-45 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack for 10 minutes. Invert onto a wire rack to cool completely. , For topping, in a heavy saucepan, combine the berries, sugar and lemon juice. Cook and stir over medium-low heat for 10 minutes or until mixture begins to thicken. Sprinkle cake with confectioners' sugar. Serve with berry topping.