Preheat oven to 350 degrees.

Combine butter and flour in food processor and blend until crumbly.

Transfer butter and flour mixture to a large mixing bowl.

Add baking powder, salt, cinnamon and ¾ cup of sugar and stir to combine.

Mix in eggs and milk and stir until all ingredients are well mixed in.

Peel and slice apples.

Grease and flour a 10-inch spring-form pan.

On a floured surface, roll out half the dough to a 10-inch circle. Put in the spring-form pan.

Top with apples, and then the second half of the dough.

Bake for 45 minutes or until a toothpick inserted in the cake comes out clean.

To make the topping, heat heavy cream and butter over medium heat until just
boiling, while stirring frequently.

Add white chocolate and Irish whiskey to a mixing bowl. Pour hot heavy cream over the white chocolate and stir until the chocolate has completely melted.

Slice and serve with sauce.