Preheat oven to 350 degrees F.

Cream butter and sugar together until light and fluffy. Add egg and mix until well combined. Add in vanilla and yogurt and stir. Mix dry ingredients together and add to batter, only mixing until just combined. Fold in apple chunks.

Spray 2 ramekins {I used the 6 ounce, 3 1/2 inch} with non-stick spray and pour batter into them equally. Bake for 30-35 minutes or until inserted toothpick comes out clean.

For the brown sugar topping, I simply combined 1/2 tablespoon flour, 1 tablespoon brown sugar, 1/4 teaspoon cinnamon, a pinch of salt and 2 teaspoons of melted butter and then crumbled it over top before baking. For an optional glaze on top, combine 3-4 tablespoons of powdered sugar and a drop or two of milk (literally a drop) and whisk until a glaze forms.