1. Preheat oven to 350.
2. Blend cheese with butter& potatos.
3. Combine egg yolks, milk& dry ingredients.
4. Add to potato mixture& stir until smooth.
5. Beat egg whites until stiff.
6. Fold in potato mixture.
7. Turn into a well greased 4c.
8. baking dish.
9. Bake until golden brown.