In a small mixing bowl, stir together the peanut butter, melted coconut oil, sugar and maple syrup. Add in the oat flour, oats, baking powder and salt and stir until well combined. Place in the refrigerator for at least 30 minutes while preparing the rest of the recipe.

Place the apples in a medium mixing bowl and add the remaining apple portion ingredients. Stir until well combined.

Preheat the oven to 350 °F (175 °C) and grease two 5" tart dishes.

Place the crumbles on a baking sheet to catch any possible spills. Bake for 30 minutes or until the topping is firm and the apples have started to bubble lightly.

Let cool for about 20 minutes before serving. Cover and keep at room temperature for up to 12 hours and then refrigerate (which prevents the topping from softening) for up to 3 days.

Before serving, prepare the peanut butter maple sauce. In a saucepan, mix together all sauce ingredients over medium heat. At first it won't appear to come together well. Stirring constantly, bring to a boil and while continuing to stir constantly, boil for about 30 seconds. It should have thickened a bit and should you have any leftovers after pouring it over your crumbles, will continue to thicken while cooling. The sauce will be too firm to pour at room temperature. To liquefy it again, reheat it on the stove over low heat, while stirring constantly, until liquid.