Line a 12-cup muffin tin with paper liners. Lightly spray liners with nonstick cooking spray.
In a large bowl, beat egg.
Add brown sugar, baking powder, vanilla, cinnamon, nutmeg, allspice, and salt. Mix well.
Whisk in milk.
Stir in apple and oats.
Pour into prepared muffin tins.
For the topping, stir together brown sugar and coconut oil in a small bowl.
Add almonds and cinnamon; stir to combine.
Sprinkle topping evenly over each oatmeal.
Bake for 20-25 min.
Oatmeal can be served warm. These also work well for make-ahead breakfasts. Simply make as directed. Store any extras covered in the fridge, warm, and enjoy.