Line a 9in spring form pan with parchment paper and butter and pre-heat oven to 350 degrees
Cream 1 cup butter, 1 cup brown sugar and 1 cup agave nectar for 2 minutes then slowly add vanilla, eggs and then oats and 1/2 of the chooped apples, mix until combined. Sift together flour, baking soda, cinnamon, nutmeg and salt. Add flour mixture to wet ingredients and mix until combined. Scoop batter into spring form pan and bake for 50 minutes or until toothpick comes out clean. Cool cake completely before topping.
For the topping: cream 2 tablespoons butter, 1 cup brown sugar and 2 tablespoons agave nectar slowly adding cream. Add the coconut and ½ of the chopped apples, mix until combined. Cover the cake to the rim with the topping and bake until golden brown and set about 30 minutes.