Combine 2 cups flour and baking powder in a medium mixing bowl. Cut in butter with a pastry blender until mixture resembles coarse meal. Sprinkle cold water evenly over surface; stir with a fork until dry ingredients are moistened. Shape into a ball; chill.
Divide dough into 3 portions. Combine 2 portions of pastry and roll to 1/8-inch thickness on a lightly floured board; fit into a greased 9- x 5- x 3-inch loaf pan.
Combine raisins, currants, and almonds in a large mixing bowl; stir well. Combine remaining 2 cups flour, sugar, cream of tartar, baking powder, spices, and pepper; mix well. Add to raisin mixture, stirring well. Add milk and brandy; stirring well. Spoon filling into prepared pastry-lined loaf pan.
Roll remaining pastry to 1/8- inch thickness; carefully place over filling, leaving a 1-inch overhang around edge of loaf pan. Seal edges and flute; cut slits in top. Brush with egg.
Bake at 225° for 3 hours or until lightly browned. Cool in pan 15 minutes. Remove from pan; place on a wire rack, and let cool completely