This Peanut Butter Banana Baked Oatmeal is one of those recipes that quickly became a weekday staple in my kitchen. I first developed this version on a hectic Sunday morning when my family needed something filling, portable, and a little bit indulgent without being overly sweet. The combination of naturally sweet ripe bananas and creamy peanut butter creates a dense, tender texture with a toasted edge that always gets rave reviews. It reminds me of early school mornings when I would slice a warm square into a lunchbox and watch my kids beam at the sight of banana and peanut butter swirls.

What makes this preparation special is how forgiving it is: you can tweak the sweetness, swap milk types, or add mix-ins without breaking the structure. The dish browns nicely around the edges and holds together so you can cut neat squares right from an 8x8-inch pan. The flavor is familiar and comforting, with a nutty richness from peanut butter and mellow banana notes that pair beautifully with a drizzle of honey. Over the years this version has become my travel breakfast of choice for road trips and potluck brunches alike.

Ingredients

• Old fashioned oats: Use 2 cups of rolled oats for the best texture. Look for a recognizable brand like Quaker or Bob's Red Mill; certified gluten-free oats are available if you need them. Rolled oats create a tender but structured crumb versus quick oats which can get too soft.
• Baking powder: One teaspoon helps the mixture rise slightly and gives a lighter bite. Make sure it is fresh for best lift.
• Ground cinnamon: Half a teaspoon adds warmth and balances the peanut butter. Saigon or Ceylon cinnamon will both work, though Saigon is bolder.
• Salt: A quarter teaspoon enhances all flavors and prevents the dish tasting flat, even though it contains sweet ingredients.
• Ripe bananas: Two medium bananas mashed (about 3/4 cup) provide natural sweetness and moisture. Very ripe bananas with brown flecks are ideal for the most banana aroma.
• Creamy peanut butter: Use 1/4 cup of a smooth, well-stirred jar such as Skippy or natural peanut butter. If using natural peanut butter, mix well before measuring to combine oils.
• Honey: Two tablespoons add a rounded sweetness and glossy top when baked; maple syrup works as an equal substitute if preferred.
• Large egg: One egg binds the mixture and gives a custard-like hold when baked; replace with a flax egg for an egg-free adaptation.
• Vanilla unsweetened almond milk: One cup keeps the mixture dairy-free and light. Any milk can be swapped here, but dairy milk will add more richness.
• Vanilla extract: One teaspoon deepens the flavor and lifts the banana notes; pure extract is recommended.
• For serving (optional): Banana slices, extra peanut butter, and honey for drizzling add a nice finishing touch and textural contrast.

Instructions

Preheat and prepare pan: Preheat your oven to 350 degrees F. Grease an 8x8-inch baking pan lightly with nonstick spray or line it with parchment paper, leaving an overhang for easy removal. A well-prepared pan ensures even browning and makes slicing clean squares easier. Mix dry ingredients: In a medium bowl, whisk together 2 cups old fashioned oats, 1 teaspoon baking powder, 1/2 teaspoon ground cinnamon, and 1/4 teaspoon salt. Whisking helps distribute the leavening and spices so the lift and flavor are uniform throughout the bake. Combine wet ingredients: In a larger bowl, mash 2 medium ripe bananas until mostly smooth, then stir in 1/4 cup creamy peanut butter until blended. Add 2 tablespoons honey, 1 large egg, 1 cup vanilla unsweetened almond milk, and 1 teaspoon vanilla extract. Whisk until fully combined; the mixture should be pourable but slightly thick. Combine wet and dry: Fold the dry oat mixture into the wet bowl until just combined. Avoid overmixing which can make the final texture gummy. Let the batter rest for 2 minutes so the oats hydrate, then pour into the prepared pan and spread evenly with a spatula. Bake: Bake in the preheated oven for 23 to 25 minutes. You are looking for the center to be set and for the edges to turn slightly golden brown. A gentle press should make the surface spring back. If using a darker pan, check at 20 minutes to prevent over-browning. Cool, slice, and serve: Remove from oven, allow to cool for at least 10 minutes to set, then cut into squares. Serve warm with banana slices and an extra drizzle of peanut butter and honey if desired. Reheating a square for 20 to 30 seconds in the microwave softens it without drying out.

Storage Tips

Store cooled squares in an airtight container in the refrigerator for up to five days. Place parchment between layers to prevent sticking. For longer storage, wrap individual squares tightly in plastic wrap and freeze in a zip-top bag for up to three months. Reheat frozen pieces in the microwave for 60 to 90 seconds or in a 350 degrees F oven for 10 minutes until warm. If the edges dry out slightly after refrigeration, a quick brush of milk or a short reheat will restore tenderness.

Ingredient Substitutions

If you need to adjust ingredients, this base is very forgiving. Swap peanut butter for almond or sunflower seed butter cup for cup; sunflower is great for nut-free needs. Replace honey with maple syrup in a 1:1 ratio. To make it egg-free, use a flax egg made from 1 tablespoon ground flaxseed mixed with 3 tablespoons water, allowed to gel for 5 minutes. For extra protein, stir in 1/4 cup of protein powder, but reduce the almond milk by 2 tablespoons so the consistency remains balanced.

Serving Suggestions

Serve warm with sliced bananas and a drizzle of warmed peanut butter and honey. For a brunch spread, offer toppings like toasted coconut, chopped roasted peanuts, yogurt, and fresh berries so guests can customize. Pair with a cup of black coffee or a smoothie for a complete breakfast. For a mid-day snack, cut smaller squares and serve alongside a protein shake to keep hunger at bay.

Cultural Background

While baked oatmeal is a relatively modern adaptation of traditional porridge, it draws on the long history of oats as a hearty grain in North American and British cooking. This combination of banana and peanut butter nods to classic American flavor pairings that are both nostalgic and practical. The concept of baking oats into a set custard-like bar likely evolved from resourceful home cooks looking for portable, oven-baked breakfasts that scale easily for families.

Seasonal Adaptations

Adapt for the seasons by stirring in autumn spices like nutmeg and allspice for fall, adding chopped apples instead of bananas, or folding in fresh summer berries and a touch of lemon zest when fruit is at peak. During the holidays, fold in 1/4 cup of finely chopped toasted pecans and a tablespoon of molasses for a more festive profile. For colder months, serve with warmed spiced maple syrup for extra comfort.

Meal Prep Tips

Make a double batch and freeze individual portions for quick breakfasts on busy mornings. I recommend cutting into squares, wrapping each in parchment, and placing them in a labeled freezer bag. For weekly prep, bake on Sunday, cool thoroughly, then portion into single-serve containers. Reheat in the microwave for 30 to 60 seconds with a few drops of milk to restore moisture, or warm in a small toaster oven for crisp edges.

There is something deeply satisfying about pulling a warm square out of the pan and sharing it with someone you love. This simple, adaptable preparation is built to be made your own, and I hope it becomes a comforting repeat in your home just as it did in mine.