You'll need rolled oats (old-fashioned or quick oats), milk (dairy or plant-based), Greek yogurt (plain or vanilla), unsweetened applesauce, chopped apples, maple syrup or honey, cinnamon, nutmeg, and a pinch of salt.
In a mixing bowl or jar, combine 1/2 cup of rolled oats with 1/2 cup of milk. Stir well to ensure the oats are fully coated in the milk. You can adjust the amount of milk based on your desired consistency.
Stir in 1/4 cup of Greek yogurt to the oat mixture. The yogurt adds creaminess and protein to the overnight oats.
Add 2 tablespoons of unsweetened applesauce to the mixture for apple flavor and sweetness. Then, add 1-2 tablespoons of maple syrup or honey, depending on your preference for sweetness. Sprinkle in 1/2 teaspoon of cinnamon, a pinch of nutmeg, and a pinch of salt for the classic apple pie flavor.
Fold in 1/2 cup of chopped apples (about half a medium apple) into the oat mixture. You can use your favorite variety of apple, such as Granny Smith, Honeycrisp, or Gala.
Transfer the oat mixture into a jar or airtight container with a lid. Make sure the oats are evenly distributed and the apples are well mixed in.
Cover the jar or container with a lid and refrigerate the overnight oats for at least 4 hours or overnight. This allows the oats to soften and absorb the flavors.
Before serving, give the overnight oats a good stir to combine any separated ingredients. You can enjoy the apple pie overnight oats cold straight from the fridge or warm them up in the microwave for a cozy breakfast. Optionally, top with additional chopped apples, a drizzle of maple syrup, and a sprinkle of cinnamon for garnish.