Heat the oven to 375F (190C).Peel and core the apples and slice into sixteenths. Toss in a bowl with the white sugar, 2 tablespoons (30 mL) of brown sugar, cinnamon, nutmeg, allspice, and cornstarch until the apples are evenly coated.

Prepare a 9 x 13-inch (23 x 33 cm) baking dish by greasing it with either butter or non-stick food spray. Place all the apples in the dish. In a second large bowl combine the remaining brown sugar, flour, and oats. Mix well. Cut the butter into small cubes and then work it into the dry mixture using a fork or pastry cutter, until the texture resembles breadcrumbs. Spread the topping mixture over the apples evenly, patting down slightly.

Transfer the baking dish onto a baking tray, to catch any sticky spillage as the crisp cooks, and bake for 35 to 45 minutes, or until the topping is brown and crisp and the apples are tender. Rest for at least 30 minutes before serving.

Top with vanilla ice cream or whipped cream.