Pour boiling water over oats, cover and let stand 20 minutes.
Cream butter and mix in sugar and brown sugar and beat until fluffy. Mix in vanilla and eggs. Add oat mixture and beat well. Add flour, baking soda, salt, cinnamon and nutmeg.
Bake at 350F for 50 to 55 minutes and leave in pan. Cover cake in frosting and broil until bubbly.