Preheat the oven to 350˚F.
Using a sharp paring knife, carefully remove the apple core by twisting the knife. Once the opening is large enough, use a spoon to scoop out more apple to make room for the filling.
Mix together oats, flour, spices, salt, ginger, and pecans. Then, stir in the butter, maple syrup, vanilla, and bourbon until well combined.
Divide the filling between the 4 apples.
Bake for 35-45 minutes (the longer they bake, the softer the apple will be; I like mine with a bit of bite).
Serve warm with vanilla ice cream and caramel for a delightful treat!