Pick your container: A jar with a lid or a lidded bowl works best. Aim for at least 12 ounces if you’re adding lots of mix-ins.

Mash or slice the banana: For sweeter, thicker oats, mash the banana in the jar. For a cleaner look and chunkier texture, slice and add later as a topping.

Add the base: Stir in 1/2 cup rolled oats, 1/2–3/4 cup milk, 1–2 tablespoons peanut butter, and a pinch of salt.

Flavor and thicken: Add 1 teaspoon chia seeds, a splash of vanilla, and cinnamon if using. Sweeten to taste with maple syrup or honey.

Mix well: Stir vigorously so the peanut butter disperses. If it clumps, microwave the jar (without metal lid) for 10–15 seconds to loosen, then stir again.

Chill: Cover and refrigerate for at least 4 hours, ideally overnight, to let the oats soften and the chia thicken.

Morning refresh: Open and stir. If it’s too thick, add a splash of milk until it’s creamy and spoonable.

Add toppings: Finish with fresh banana slices, a drizzle of peanut butter, a sprinkle of chopped nuts, or a few chocolate chips.

Serve cold or slightly warmed: Eat straight from the fridge, or warm gently in the microwave in 15–20 second bursts, stirring between intervals.