Grease an 8x8 or 9x13 baking dish. (Double the topping amounts for a 9x13.)
Peel, core and slice apples and cover the bottom of your dish at least an inch deep.
Combine the sweetener and spices in a medium bowl, then fold half of that mixture in with your apples in the baking dish along with all of the lemon juice. Also add optional add-ins at this time.
Mix the oats, flour, and salt with the remaining sugar-spice mixture in the bowl.
Cut the butter into the mixture and add in the optional liquid.
Spread the topping over the apples.
Bake uncovered at 350°F for 45 minutes OR 375°F for 30 minutes or until the apples are soft.