Preheat the oven to 325 degrees.
for Apples:
Mix the following together and set aside:
3 sm. apples or 2 larger ones, peeled, cored
Juice from 1 large lemon
and diced 2 tsp. cornstarch
3-4 Tbsp. unrefined sugar
1/2 tsp. cinnamon
for Crumb Topping:
Mix the following together in a separate bowl:
2 Tbsp. dark brown sugar
1/4 tsp. cinnamon
¼-1/3 c. chopped walnuts
2 Tbsp. sugar
1.5 cup flour
Pinch salt
Add 1/2 cup melted butter, cooled,  the dry mix above and knead with fingers until it becomes crumbs, then set aside.
for Cake Batter:
2 Tbsp. Greek yogurt or sour cream
2 eggs
1/2 cup sugar
1/2 tsp. baking soda
2 tsp. vanilla
6 Tbsp. softened butter
1/2 tsp. baking powder
1 cup flour
1/2 tsp. cinnamon
Pinch salt
Beat together softened butter and sugar until creamy. Add yogurt, vanilla, and eggs. Mix dry ingredients separately then beat into wet mixture. Don't overmix. Stir apples into batter, being careful not to add the liquid that will have settled at the bottom of the apples while they were sitting (I.e., drain first or lift out with slotted spoon). To assemble, spoon cake batter into greased 10” bundt pan. Crumble crumb topping over batter (should be enough to cover generously without much batter being visible through it). Bake for 45-50 min., or until top is lightly browned & a toothpick inserted into the center of cake comes out clean - it will probably still be a little moist from the apples. Cool before serving.
submitted by member Sarah Rich