Heat oven to 350 degrees F. Grease and flour an 8-inch square pan.
Mix flour, sugar, baking powder and salt.
Cream butter to soften. Add flour mixture, milk and vanilla extract. Mix
until all flour is moistened; then beat 2 minutes at medium speed of electric
mixer, scraping bowl occasionally. Add egg; beat 1 minute longer. Stir in 2/3
cup of the coconut. Pour into prepared pan.
Bake for about 40 minutes or until cake tester inserted comes out clean.
Cool in pan 10 minutes; remove and finish cooling on rack.
Split cake into 2 layers. Reserve 1 tablespoon of jam; mix remaining jam
with 2/3 cup coconut and spread between layers. Cover top and sides of cake
with whipped topping and remaining coconut.