Ingredients:-

2 large, firm cooking apples

3 tablespoons unsalted butter

3 tablespoons brown sugar

3/4 teaspoon cinnamon

1 tablespoon flour

1 tablespoon rolled oats

Salt

Cooking oil

Ice cream, for serving (optional)

Method:-

(1) Heat the oven to 400°F.

(2) In a small saucepan melt 1 tablespoon of butter. Once cooled add 1 tablespoon brown sugar and 1/2 teaspoon cinnamon. Set aside.

(3) Peel the apples to remove all the skin.

(4) Slice the apples in half from top to bottom.

(5) Core the apples: Use a melon baller or spoon to remove the apple cores.

(6) Cut slices in the apples, leaving the bottom intact: Place the apples cut-side down on a cutting board. Cut slices into the apple, 1/4-inch apart, stopping just before you cut through the bottom. 

(7) Stir together the butter mixture. Use a pastry brush to spread the butter mixture over top of the apples and into the slices.

(8) Bake the apples: Brush a thin layer of cooking oil over the inside of a baking dish. Place the apples in the baking dish, flat-side down. Cover the baking dish with tinfoil, and bake for 20 minutes.

(9) Prepare the streusel: Cut the remaining tablespoon of butter into cubes. Add it to a bowl, along with 2 tablespoons brown sugar, 1/4 teaspoon cinnamon, flour, oats, and a pinch of salt. Use your fingers or a fork to blend the ingredients together.

(10) Top the apples with streusel: After the apples have finished baking, remove the baking dish from the oven. Use a fork to carefully spread the streusel over top of the apples. Work the streusel between the slices as well.

(11)  Increase the oven temperature to 425°F. Place the baking dish back in the oven and bake, uncovered, for 15 minutes more.

(12)  Remove the baking dish from the oven. Cool the apples for about 5 minutes before serving.