Combine the oil, sugars, flour, and salt. Mix thoroughly.

Set aside 3/4 cup of the mixture for a streusel topping.

To the remaining mixture, add the buttermilk, egg, baking soda, cinnamon, and nutmeg. Mix.

Pour batter into a greased 9×13 pan.

Crumble the reserved streusel mixture on top. (Note: If the streusel topping is clumpy instead of crumbly, add flour and granulated sugar, alternately, until the desired texture is reached. I usually add 2 tablespoons each of flour and sugar.)

Bake at 350 degrees for 25 minutes, or until a toothpick inserted comes out clean.

In a small bowl, combine powdered sugar and milk. While the cake is still warm, drizzle the glaze on top.

Tip: if you do not have buttermilk, use 1 tablespoon of lemon juice and enough milk to equal 1 cup. Set aside for 5 minutes, then use.