- 5 apples – peeled, cored, quartered, and cut into 1/4-inch slices
- 1/2 lemon, juiced
- 1/2 cup all-purpose flour
- 1/2 cup rolled oats
- 1/2 cup wheat and barley nugget cereal (such as Grape-Nuts®)
- 1/2 cup melted butter
- 1/4 cup white sugar
- 1/4 cup brown sugar
- 2 tablespoons butter
- 1/3 cup brown sugar
- 1/3 cup white sugar
- 1/4 teaspoon cinnamon
- 1 tablespoon water
- Preheat the oven to 375 degrees F (190 degrees C).
- Toss sliced apples with lemon juice to prevent browning.
- Mix flour, rolled oats, wheat and barley nugget cereal, melted butter, 1/4 cup white sugar, and 1/4 cup brown sugar together in a large bowl.
- Melt 2 tablespoons butter in a large skillet over medium heat. Stir 1/3 cup brown sugar, 1/3 cup white sugar, and cinnamon into melted butter until sugar begins to dissolve, 3 to 4 minutes. Add apples and water; continue cooking and stirring until apples soften and are coated with sauce, 4 to 5 minutes.
- Pour apples and sugar mixture into a 2 quart baking dish. Sprinkle topping evenly over the apple filling.
- Bake in the preheated oven until the top is browned and the filling is bubbling up around the edges, 25 to 30 minutes. Cool for 10 to 15 minutes.