Preheat oven to 350°F (175°C). Grease a 9×13-inch baking dish.

Pour boiling water over oats and let soak while you prepare the rest.

Cream butter and sugars together until fluffy. Add eggs, beating well.

Stir in soaked oats.

Sift together flour, baking soda, salt, cinnamon, and nutmeg. Add to wet ingredients.

Pour batter into the prepared dish and bake for 30-35 minutes.

While the cake bakes, melt the butter for the topping, then stir in brown sugar, milk, coconut, and pecans.

Spread the topping over the hot cake and broil for 2-3 minutes until golden and bubbly.