1. Combine the flour, white sugar, brown sugar and salt in a large bowl. Stir to combine.
2. Cut the room temperature butter into the flour mixture until you have coarse crumbs. (I started cutting the butter into the flour with a pastry blender and finished cutting it in with my fingers. Rubbing the mixture between my fingers and thumbs.)
3. Remove 1 cup of crumbs from the large bowl of crumbs, place the one cup of crumbs in another large bowl,add the cinnamon to it, stir to incorporate. Set aside.
4. Grease a 13x9 inch baking pan. Place half the large batch of crumbs (about 4 cups) into the baking pan. Press onto the bottom of the baking pan to make a solid layer. Bake at 350 degrees for 10 minutes.
5. While the bottom layer is baking, peel, core and cube the apples, sprinkle with 2 teaspoons lemon juice. Place in the bowl with the reserved 1 cup of crumbs, toss to coat.
6. Take the baking pan from the oven, place the apples on top of the baked bottom layer. Sprinkle with the remaining 4 cups of crumbs. Bake uncovered for 45 minutes or until the crumble topping is golden brown and apples are tender.