• Place aluminum collar at back half of a 6-quart slow cooker (about 4-inches tall and 14-inches long, 4 layers thick). If desired, line the insert with a slow cooker liner. Spray with cooking spray.
• Add 8 sliced apples, 1 Tablespoon lemon juice to a large mixing bowl and toss to combine. Add ⅓ cup brown sugar, 2 teaspoons cinnamon and pinch of salt and toss until completely combined. Pour the entire mixture into the bowl of the slow cooker and spread everything out in an even layer.
• In the same bowl you mixed the apples, whisk together 1 cup oats, ½ cup almonds, ½ cup flour, ½ cup brown sugar, 1 teaspoon cinnamon and a pinch of salt until evenly combined. Drizzle the 4 Tablespoons melted butter over the mixture and then whisk until combined.
• Place a dish towel or a few paper towels on top of the slow cooker, and place the lid on top of the towel(s). the towels will help soak up the condensation that forms along the top of the lid and keep the oat crumble nice and crisp.
• Cook on high for 3-4 hours (this option produces a crisper topping), or on low for 6-8 hours. Remove the lid and towel(s) and serve immediately.

Cook's Note:

• Since slow cookers heat up to different temperatures, if this is your first time using the towel method, check it an hour into cooking to ensure the towl is not too hot. I've used paper towels to absorb moisture in recipes for years and many professionally recommended recipes use this method as well. I'm required to advise you that you use this method at your own risk.