Grease bottom of a pan or cast iron skillet with coconut oil. Add sliced peaches, cornstarch, lemon juice, sugar, and vanilla. Mix well and set aside.
In a medium-sized mixing bowl, add all the ingredients for the oat topping except for the oats. Cut the solid coconut oil into the mixture until fully incorporated. Stir in oats.
Pour oat topping over peaches. Bake for 35-40 minutes until the top is nice and golden brown.