Preheat the oven to 350 degrees. Butter a 9 x 14 x 2 inch oval baking dish (you can also use a large rectangle dish).

Peel, core and cut the apples into medium size wedges. Combine the apples with the zest, spices, sugar and juices. Let it rest (in a bowl), while you make the topping.

To make the topping, combine the flour, sugars, salt, oatmeal and cold butter in a food processor or mixer. Mix or pulse on low speed until it is crumbly and the butter is the size of peas. Spread the topping on the apples which you have placed in the buttered baking dish. Bake for one hour.

Serve warm with or without ice cream.