Step 1

Preheat oven to 350 degrees. Prepare a 9x13 baking dish with butter and flour.

Step 2

Combine apples and sugar in a large mixing bowl. Add in oil, eggs, and vanilla. Stir to combine.

Step 3

In a separate bowl, combine flour, baking powder, baking soda, cinnamon, nutmeg, and salt. Add this mixture to the apple mixture, add milk and stir to combine. Mix in walnuts.

Step 4

Spread batter into prepared baking dish, and bake for 30 minutes, or until a toothpick comes out clean.

Step 5

While waiting for the cake to cool, make the frosting. Beat cream cheese until smooth, and add butter a little at a time while continuing to beat. Mix in vanilla and brown sugar, continue to beat until sugar has dissolved, and frosting is light and fluffy.

Step 6

When cake has completely cooled, frost with brown sugar cream cheese. Optional: sprinkle additional chopped walnuts on top for garnish. Refrigerate once frosted.