Chocolate Hazelnut Crunch Cake

Hazelnut Crunch Layer Cake
Cake:
1/2 cup butter
1/3 cup cocoa powder
2/3 cup coconut flour
1/4 cup granulated erythritol
1 tsp baking powder
1 tsp baking soda
1/2 tsp salt
8 eggs
1 tsp vanilla or hazelnut extract
1/2 tsp liquid stevia extract
3/4 cup almond milk
Hazelnut Cream:
1/2 cup hazelnuts, toasted and husked
2 tbsp vegetable or nut oil
2 tbsp cocoa powder
1 tbsp erythritol, preferably powdered
1/4 tsp vanilla
1/4 cup whipping cream
Chocolate Ganache:
5 oz high % cacao chocolate (I use Lindt 85%)
4 tbsp butter
1/4 cup toasted, husked hazelnuts, coarsely chopped
For the cake, preheat the oven to 350F, and line two 8-inch round cake pans with parchment paper. Grease paper and sides of pan.
In a small saucepan over low heat, melt butter. Whisk in cocoa powder until smooth and set aside.
In a medium bowl, whisk together coconut flour, erythritol, baking powder, baking soda, and salt. Set aside.
In a larger bowl, beat eggs with vanilla or hazelnut extract and stevia extract until frothy. Add butter/cocoa mixture to eggs and beat until combined. Add half of coconut flour mixture and beat on low for a few moments, then add almond milk and beat in thoroughly. Add remaining coconut flour mixture and beat on low, then use a rubber spatula to stir and make sure all ingredients are well combined.
Divide batter evenly between prepared cake pans and smooth the tops. Bake for 25-30 minutes or until tops are set and tester inserted into the center comes out clean. Cool in pan 10 minutes, then flip out onto wire rack to cool completely.
For the hazelnut cream, grind hazelnuts in a food processor until finely ground and beginning to clump together. Add remaining ingredients and continue to process until creamy and smooth, scraping down sides of processor with a rubber spatula as needed*.
In a small bowl, beat whipping cream until it forms soft peaks. Stir in hazelnut mixture until fully combined.
Spread hazelnut cream on one layer of cake, then sprinkle with 2 tbsp of chopped, toasted hazelnuts. Top with second layer of cake.
For the ganache, in a small saucepan over low heat, melt butter and chocolate together. Stir until completely smooth. Pour about half over the top of prepared cake and spread with an offset spatula. Pour remaining ganache over top of prepared cake and spread to the edges, allowing some ganache to drip down the sides. Sprinkle with remaining chopped hazelnuts.
*Note: this is essentially homemade nutella. I made a larger batch of it a few days ahead, and when it came time to make the cake, I used about 1/2 - 3/4 cup to mix with the whipped cream. If you make it ahead of time and store it in the fridge, you will want to bring it to room temperature, or even a bit warmer by heating gently in your microwave, before mixing it into the whipped cream.