1Heat oven to 350°F. Grease 8-inch square pan with shortening; lightly flour.
2In small bowl, mix 1 3/4 cups of the flour, the baking powder, cinnamon, ginger, nutmeg, baking soda and salt. In medium bowl, beat brown sugar and 1/2 cup butter with electric mixer on medium speed 3 minutes or until light and fluffy. Beat in eggs, one at a time. On low speed, beat in molasses. Add flour mixture to butter mixture alternately with 1/2 cup buttermilk, beating after each addition just until smooth. Mix remaining 1/4 cup flour and the apples. Fold into batter. Pour into pan.
3Bake 45 to 50 minutes or until toothpick inserted in center comes out clean. Cool completely on cooling rack, about 2 hours.
4In medium bowl, beat powdered sugar, 1/4 cup butter, 2 tablespoons buttermilk and the vanilla with electric mixer on medium speed 2 minutes or until smooth. Frost cake. Sprinkle with additional nutmeg, if desired. Cut into 4 rows by 4 rows.