Preheat oven to 350F. Cream butter and sugar. Add flour and juice of lemon. Add milk and beaten egg yolks. In a separate bowl, beat egg whites until stiff.
Slowly fold egg whites into above mixture. Pour into a Pyrex bread pan and place this dish into another dish of hot water (about one inch of water should be in the pan). Bake slowly in oven 1 hour. Remove from oven and from pan of hot water. Let sit at least 15 minutes before serving.
This makes a light and fluffy cake-like topping with a soft pudding on the bottom. May also be served cold.
Serve in parfait dishes.
Cajun Country -- New Iberia, Louisiana