These Banana Oatmeal Cookies might be one of the easiest homemade cookies you can make. One ripe banana, oats, creamy peanut butter, dark chocolate chips, and walnuts come together in one bowl—no mixer and no complicated dough chilling required.
They're naturally soft and chewy rather than crisp like a traditional butter cookie. Banana provides moisture and sweetness, peanut butter makes them rich and satisfying, and dark chocolate adds little pockets of melted chocolate throughout.
The recipe makes about 7 generously sized cookies, so it's perfect when you want a small batch. Double it for meal prep or to keep a few extra cookies around for quick breakfasts and snacks.
Ingredients
For the Cookies
- 1 large very ripe banana, mashed
- 1 cup (90g) old-fashioned rolled oats
- ¼ cup (64g) creamy natural peanut butter
- ½ tablespoon ground flaxseed
- ¼ teaspoon baking powder
- ½ teaspoon pure vanilla extract
- Pinch of salt
- 1–2 tablespoons pure maple syrup, to taste
- ¼ cup (43g) dark chocolate chips
- 2 tablespoons chopped walnuts
For Topping
- Extra dark chocolate chips, optional
- Flaky sea salt, optional
How to Make Banana Oatmeal Cookies
Step 1 – Preheat the Oven
Preheat the oven to 350°F (175°C).
Line a baking sheet with parchment paper.
Step 2 – Mash the Banana
Place the banana in a medium mixing bowl.
Mash thoroughly with a fork until mostly smooth.
For the best flavor and natural sweetness, use a banana with plenty of brown spots.
Step 3 – Add the Peanut Butter
Add the peanut butter and maple syrup.
Stir until thoroughly combined with the banana.
Add:
- Vanilla
- Ground flaxseed
- Baking powder
- Salt
Mix again.
Step 4 – Add the Oats
Stir in the rolled oats until evenly coated.
The mixture should be thick, moist, and scoopable rather than runny.
Let it stand for about 5 minutes. This gives the oats and ground flaxseed a little time to absorb moisture from the banana.
Step 5 – Add Chocolate & Walnuts
Fold in the dark chocolate chips and chopped walnuts.
Reserve a few chocolate chips for decorating the tops if desired.
Shape the Cookies
Use a cookie scoop to portion the mixture onto the prepared baking sheet.
You should get approximately 7 cookies.
Leave a little space between each one.
These cookies don't spread very much during baking, so use the back of a spoon or slightly damp fingertips to gently flatten each cookie into the shape and thickness you want.
Press a few additional chocolate chips into the tops.
Bake
Bake at 350°F (175°C) for 10–12 minutes, or until the edges are lightly golden and the centers look set.
For softer cookies, stay toward the lower end of the baking time.
For slightly firmer edges, give them another minute or two while watching carefully.
Cool
Remove the baking sheet from the oven.
Immediately sprinkle the warm cookies with a tiny amount of flaky sea salt, if desired.
Let them cool on the baking sheet for 5–10 minutes.
They're quite soft when hot, so allowing them to set before moving them helps prevent breakage.
Transfer to a wire rack and enjoy warm or completely cooled.
Chef's Tips for the Best Banana Oatmeal Cookies
- Use a very ripe banana. It's responsible for much of the sweetness.
- Stir natural peanut butter thoroughly before measuring it.
- Use old-fashioned rolled oats for a satisfying chewy texture.
- Don't skip the salt—it balances the banana, maple, and chocolate.
- Let the mixture rest for about 5 minutes if it seems loose.
- These cookies won't spread like traditional cookies, so flatten them before baking.
- Chop the walnuts relatively small so every cookie gets some.
- Dark chocolate balances the sweetness particularly well.
- Don't overbake if you want a soft, moist center.
- Let the cookies set on the baking sheet before moving them.
The Secret to the Best Texture
These aren't traditional flour-and-butter oatmeal cookies.
Their structure comes primarily from oats, banana, peanut butter, and ground flaxseed.
The banana provides moisture and helps bind everything together, while the oats absorb that moisture during resting and baking. Ground flaxseed absorbs additional liquid and helps the cookies hold their shape.
That's why a short 5-minute rest before scooping can make a noticeable difference, especially when using a particularly large or juicy banana.
How Sweet Should They Be?
Start with 1 tablespoon maple syrup if your banana is extremely ripe and you're adding chocolate chips.
Use 2 tablespoons if you prefer sweeter cookies or your banana isn't particularly ripe.
You can also omit the maple syrup for a less-sweet breakfast-style cookie, although the final flavor will depend heavily on the sweetness of your banana.
Delicious Variations
Double Chocolate Banana
Add 1 tablespoon unsweetened cocoa powder and a few extra chocolate chips.
Peanut Butter Banana
Skip the walnuts and drizzle a little warmed peanut butter over the cooled cookies.
Banana Pecan
Replace the walnuts with chopped toasted pecans.
Cinnamon Banana
Add ½ teaspoon ground cinnamon and a tiny pinch of nutmeg.
Blueberry Banana
Replace the chocolate chips with dried blueberries.
Coconut Chocolate Chip
Add 2 tablespoons unsweetened shredded coconut along with the chocolate chips.
Raisin Walnut
Replace the chocolate chips with raisins for a more classic oatmeal-cookie flavor.
Optional Crispy Walnut Trick
For stronger walnut flavor, toast the chopped walnuts before adding them.
Spread them in a dry skillet over medium-low heat and cook for approximately 2–4 minutes, stirring frequently, until fragrant.
Cool completely before folding them into the cookie mixture.
This small step makes their nutty flavor much more noticeable.
What to Serve With Banana Oatmeal Cookies
These cookies work particularly well with:
- Hot coffee
- Cold milk or plant milk
- Greek yogurt
- Fresh berries
- Sliced banana
- Peanut butter
- Vanilla yogurt
For breakfast, pair two cookies with Greek yogurt and fresh berries.
For dessert, serve one slightly warm so the dark chocolate chips become soft and melty.
Make-Ahead Tips
The easiest approach is to bake the entire batch and refrigerate or freeze the finished cookies.
Because mashed banana begins oxidizing and releasing moisture, this isn't a cookie dough I'd recommend leaving uncooked in the refrigerator for several days.
For a larger batch, simply double all the ingredients.
Storage
Room Temperature
Store in an airtight container for about 1 day if your kitchen is cool.
Because these cookies are very moist and fruit-based, refrigerator storage is better for longer periods.
Refrigerator
Keep in an airtight container for up to 4–5 days.
Freezer
Freeze the completely cooled cookies in an airtight freezer-safe container for up to 2 months.
Place parchment paper between layers to prevent sticking.
How to Reheat
Microwave one refrigerated cookie for approximately 8–12 seconds.
The cookie will soften and the chocolate chips will become slightly melty again.
Frozen cookies can be thawed overnight in the refrigerator or briefly warmed in the microwave.
Notes
- Makes approximately 7 medium-to-large cookies.
- Double the recipe for about 14 cookies.
- Natural peanut butter works best when thoroughly stirred.
- These cookies are naturally soft and chewy, not crisp.
- Their sweetness depends strongly on the ripeness of the banana.
- If your mixture seems unusually wet, add 1–2 tablespoons additional oats and let it rest for 5 minutes.
- If it's unusually dry, add a small splash of milk.
- For the best finish, press a few visible chocolate chips into each cookie before baking and add just a tiny pinch of flaky sea salt while they're still warm.