Preheat oven to 350°F.
Add all of the ingredients for the topping, except for the butter, to a medium-sized bowl and stir to combine.
Add the cold butter and use a pastry cutter or fork to cut the butter into the dry ingredients until the mixture is crumbly and comes together. Set aside.
Combine all the ingredients for the apples and stir together so that the apples are well coated, then pour the mixture into an 8 or 9 inch square dish.
Sprinkle the topping evenly over the apples.
Bake for about 40 minutes, until the topping is golden around the edges and the apples are tender. Allow to cool for about 15 minutes prior to serving.

Notes

Storage: Once cooled, refrigerate leftovers in an airtight container for up to 4 days.
Reheating: Microwave individual helpings for 1-2 minutes, depending on size.
Make Ahead: Cover well and store in the fridge. Reheat in a 350°F oven for 15 minutes, or until desired temperature is reached.
Freezing: Store in freezer-safe container or wrap tightly in two layers of plastic wrap. Enjoy within 3 months and thaw in the fridge before reheating.
Nutrition
Serving Size: 1 serving
Calories: 454
Sugar: 41.7 g
Sodium: 109.4 mg
Fat: 19.6 g
Carbohydrates: 66.3 g
Protein: 3.8 g
Cholesterol: 50.8 mg
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