Preheat the oven to 375F and grease an 8″x8″ baking pan with butter.
Peel, core and slice the apples and place into a bowl. Sprinkle the lemon juice over the top and toss to coat. This helps the apples not to turn brown while you’re making the crumble.
Sprinkle the sugar and cinnamon over the apples and mix to coat all of the apples.
Crumble
Combine the flour, sugar, cinnamon, and nutmeg.
Add the cold, sliced butter and mix. I find it’s easiest to crumble it with my fingers and work the butter into the dry ingredients. Keep mixing until everything is combined and there are no big chunks of butter left.
Place the apples into the greased pan and then sprinkle the crumble on top until all of the apples are coated with crumble.
Bake at 375 for 1 hour or until the apples are soft and bubbly and the top has crisped.