International Dessert recipe from the Wikibooks Cookbook.
6 cups sliced and cored baking apples (for example, Granny Smith) ½ cup (100 g) all-purpose flour ½ cup (100 g) rolled oats ¾ teaspoon (3 g) cinnamon ⅓ cup (75 g) cold butter or cold margarine ⅔–¾ cup (120–150 g) brown sugar
In a medium bowl stir together flour, brown sugar, and oatmeal. If the room temperature is a bit warm, you should cool this mixture in the fridge. Prepare the apples. This should be completed before mixing butter into the topping. It is helpful to choose apples that do not brown quickly; Granny Smith apples are a good choice. Do not use Red Delicious apples; they turn to mush. Place the apples into a 9-inch (23 cm) square baking dish; glass is best. Add the butter or margarine to the topping. Mix it via a slicing action, so that the butter or margarine forms tiny little chunks and does not melt or smear. A pair of butter knives, used like scissors, is good for this. You must work quickly once you start this step. Sprinkle the topping onto the apples. You may pat it down just a bit. Bake for about 30 minutes in a 375 °F (190°C) oven. Do not remove the crisp before the top is dark brown. Black spots indicate burning. It is better to burn a few small spots, which you can then remove, than to risk undercooking the topping.