1. Cream the 1/2 cup butter and blend in brown sugar and vanilla. 2. Add flour and mix thoroughly. 3. Press into bottom of 9 cake pan. 4. Bake 15 minutes at 350 degrees F. 5. Let cool 5 minutes. 6. Spread with crushed pineapple. 7. Beat together all the topping ingredients and spread over crushed pineapple/. 8. Return to oven and bake 30 minutes more. 9. Cool- cut into squares. 10. Store in fridge.