Mash the banana: Peel 1 large ripe banana and place it in a medium bowl.Mash it well with a fork until mostly smooth.
Mix the wet ingredients: Add 1 cup Greek yogurt, 1 cup milk, 2 teaspoons honey (or maple syrup), and 1 teaspoon cinnamon to the bowl.Whisk until smooth and well combined.
Add the oats and chill: Add 1 cup rolled oats. Stir until all the oats are coated.Cover the bowl or divide the mixture into two jars. Refrigerate for at least 6 hours, or overnight.
Serve: Stir well before eating. Serve straight from the fridge, or warm gently in the microwave for 30 seconds to 1 minute if you prefer them warm.Top with nuts, fresh fruit or an extra drizzle of honey if you like.
Substitutions
Rolled oats –> Quick oats for a softer texture, or certified gluten-free oats if needed.
Ripe banana –> Mashed pear, applesauce, or a few spoonfuls of pumpkin purée.
Greek yogurt –> Low-fat Greek yogurt or skyr for more protein, or thick soy or coconut yogurt for vegan.
Milk –> Almond, oat, or soy milk for dairy-free, or extra yogurt for a thicker result.
Honey or maple syrup –> Date syrup, agave, or skip it if the banana is very ripe.
Cinnamon –> Nutmeg, pumpkin spice, or a small splash of vanilla.
Storage
Store the oats in an airtight container in the refrigerator for up to 3 days, or freeze in individual portions and thaw overnight in the fridge before eating.