Make the pastry cream: Whisk together sugar, cornstarch, salt and cinnamon. Beat the eggs well until blended and whisk into sugar-salt mixture. Heat the half and half until simmering, stirring consistently.

Continuously whisking, slowly pour the half and half into the sugar-egg mixture to temper. Continue slowly adding half and half to egg mixture. Pour blended mixture back into the pot used to heat up the half and half, lower heat a bit and stir constantly, whisking to prevent lumps from forming. Cook until mixture is very thick (10-15 minutes) – it will further thicken once refrigerated. Don’t overcook or cream will solidify, separate and be grainy when chilled.

Pour pastry cream through a sieve or chinoise into a bowl for extra smoothness, and place bowl over an ice bath and whisk to cool immediately. Store in fridge for at least 30 minutes until using.

Make the crust: Preheat oven to 350F. Grease baking dish with room temperature butter. Whisk together flour, sugar, coconut, baking powder and salt. Add vanilla into melted butter and whisk into dry ingredients. Mix until incorporated and distributed. Crust will be crumbly, but cohesive. Press lightly into dish. Blind bake crust 15 minutes at 350F, until surface is golden. Let cool for at least 30 minutes.

Make the filling and topping: Mix sugar, cinnamon and vanilla into fruit to coat. Set aside. Mix yolk into sour cream until fully combined and set aside.

Assemble the kuchen: . Spread a thin layer of chilled pastry cream atop crust (about 4 tablespoons). Arrange apples in a fan shape or circular motion and dot cranberries over top. Drizzle sour cream/egg topping lightly over fruit with a fork.
4. Bake kuchen for 30 minutes at 350F, rotating halfway until topping is set and golden. Let cool for at least 30 minutes before serving