- 1/2 cup (1 stick) unsalted butter at room temperature
- 1/2 cup sugar
- 2 large eggs
- 3 Tbsp milk or cream
- 1 1/4 cups all purpose flour
- 1 tsp baking powder
- 1 tsp cinnamon
- 1/8 tsp salt
- about 3 Granny Smith apples, peeled and thinly sliced
- confectioner’s sugar for dusting
- 3/4 cup flour
- 1/4 cup old fashioned rolled oats
- 6 Tbsp unsalted cold butter, cut in small pieces
- 1/2 cup sugar
- 6 large egg yolks
- 6 Tbsp sugar
- 1 1/2 C. whole milk
- 1 1/2 tsp vanilla
- Set the oven to 350F
- Make the custard sauce ahead of time. Bring the milk to a simmer over medium heat. Meanwhile whisk the yolks and sugar until pale. Drizzle a little of the hot milk into the egg mixture, whisking all the time. Drizzle a little more, then transfer that back into the pan of hot milk and continue cooking, stirring constantly, until the mixture coats the back of a spoon. Don’t overcook or it can curdle. Stir in the vanilla. Refrigerate the custard sauce until needed.
- To make the streusel topping, blend the bits of butter into the flour, sugar, and oats until the butter is incorporated and the mixture has a coarse crumbly texture. Put in the refrigerator.
- To make the cake, grease a 9 inch round spring form pan.
- Cream together the butter and sugar until light and fluffy. Beat in the eggs, one at a time.
- Whisk together the flour, baking powder, cinnamon, and salt. Fold the dry ingredients into the butter/sugar mixture, along with the milk or cream.
- Spoon the batter in to the pan, and smooth out evenly. Top with the sliced apples, and then the streusel topping.
- Bake for about 50 minutes to an hour, until the top is lightly browned and a toothpick comes out without wet batter clinging to it.
- Let cool a bit in the pan before removing. Dust with confectioner’s sugar before serving.