Preheat oven to 325F. Grease a 9x13-inch baking pan with non-stick cooking spray; set aside.

In a medium mixing bowl, sift together the flour, baking soda, cinnamon, nutmeg, and salt; set aside.

In a large mixing bowl, beat together the vegetable oil, granulated sugar, and brown sugar with an electric mixer on medium speed. Beat in the vanilla and the eggs one at a time.

Add the dry mixture a little at a time, mixing well between each addition. Note: the batter will be very thick.

Using a sturdy wooden spoon, fold the apples into the batter.

Spread into the prepared 9x13-inch pan and bake at 325F for 50-60 minutes, or until a toothpick inserted into the center comes out clean.

While the cake is baking, make the frosting. Add all the ingredients for the frosting to a medium saucepan. Heat over medium heat, stirring often, until the mixture begins to simmer. Remove from the and cool for 5 minutes.

Pour the frosting over the cake while it’s still warm.

Slice the cake and serve.