Preheat oven to 350 degrees.
Add oats, applesauce, honey, chia seeds, cinnamon and salt to a bowl and mix until combined.
Spray muffin tin with cooking spray.
Add an even amount of oat mixture to muffin tin to make 6 oat cups.
Use your fingers or a spoon to press the mixture into the sides and base of the muffin tin.
Bake for 12-13 minutes.
Let it cool in the muffin tin for about 10 minutes before using a butter knife to remove the oatmeal cups.
Let the cups cool completely before filling with yogurt and diced apples.