In a bowl, cream butter and sugar. Beat in eggs. Stir in banana, pineapple and coconut (add pineapple extract now if using). Combine dry ingredients; stir into creamed mixture just until combined. Spoon into a greased 8-in. x 4-in. loaf pan.
Bake at 350-f degrees for 65-70 minutes or until toothpick test comes out clean.