Lunch Lady Peanut Butter Bars taste just like the ones from school but even better with a soft, chewy base, melty peanut butter, and rich chocolate frosting.
If you’re looking for no-bake peanut butter bars, try these Peanut Butter Bars.
author’s note
Sweet And Nostalgic Peanut Butter Bars!
Old-school cafeteria peanut butter squares started with a soft peanut butter oatmeal cookie bar, topped with creamy peanut butter and chocolate fudge frosting.
They’re no longer served in schools due to peanut allergy concerns, but I grew up on these. They were my favorite lunchtime treat, and I grabbed one every chance I could.
Now, they’re a family favorite and my go-to dessert for feeding a crowd. This recipe makes a full sheet pan of bars, which means I can claim half for myself and still have plenty to share.
What Pan To Use
These bars require a specific pan to work and unfortunately, the bars won’t turn out well in different sized pans; this part of the recipe is very particular.
We are looking for a 17 x 12.25-inch jelly roll pan.
Once you’ve got the perfect pan, it’s time to make these Lunch Lady Peanut Butter Bars!
There are three elements to these bars:
- The chewy and soft oatmeal cookie base
- Peanut butter topping
- Chocolate fudge buttercream frosting
Let’s break down each below!
Lunch Lady Peanut Butter Bars Ingredients
| Ingredient | Swap or Tip |
|---|---|
| Old-fashioned oats | Do not use quick oats. They absorb too much liquid and make the bars dry. |
| Creamy peanut butter | Use a creamy peanut butter you love. Avoid natural peanut butter that separates. |
| Brown sugar | Light or dark brown sugar both work well in these bars. |
| Butter | Use unsalted butter so you can control the salt level. |
| Cocoa powder | Use natural cocoa powder for a lighter chocolate flavor or Dutch process for a richer chocolate frosting. |
| Powdered sugar | Sift if lumpy so the frosting turns out smooth and creamy. |
| Vanilla extract | Adds depth to both the bars and frosting. Use pure vanilla for the best flavor. |
How To Make Lunch Lady Peanut Butter Bars
- Make dough: Cream butter and sugars until smooth. Beat in eggs and vanilla, then mix in oats, peanut butter, flour, baking soda, and salt.
- Press into the pan: Spread dough evenly in a lined jelly roll pan.
- Bake: Bake until the edges are lightly golden but the center still looks soft.
- Pb layer: Warm peanut butter until pourable. Drizzle over the cookie base and spread.
- Make frosting: Beat butter, cocoa powder, sugar, milk, and vanilla until smooth.
- Frost and slice: Spread frosting over the bars and cut into squares once cooled.
Quick Tip
What consistency should softened butter be? It should be soft enough to leave a finger indent with gentle pressure but not so soft that it squishes or crushes the packaging.
Lunch Lady Peanut Butter Bars Recipe Tips
- Use fresh ingredients. Fresh, soft brown sugar and active leavening agents make the cookie bars softer and better.
- Stick with old-fashioned oats. Quick oats absorb more liquid and act like flour, making bars dry and less flavorful. This recipe needs old-fashioned oats to work.
- Switch it up. Try Lunch Lady Peanut Butter Brownies by topping brownies with peanut butter and chocolate buttercream.
Storage
- These lunch lady peanut butter bars store nicely in an airtight container at room temperature. They are the best and softest within 2-3 days of making but will last (properly stored) for about 5-7 days.
- These bars freeze well. Wrap each bar individually in plastic wrap and then store the wrapped bars in a large plastic bag or freezer-safe container. Thaw bars overnight in the fridge. Freeze for up to 3 months.
More Chocolate and Peanut Butter Treats:
Desserts
Peanut Butter Chocolate Pie
Desserts
Chewy Peanut Butter Cookies
Desserts
Peanut Butter Brownie Bites
Lunch Lady Peanut Butter Bars
Lunch Lady Peanut Butter Bars are a must-try! A chewy peanut butter oatmeal base gets topped with melty peanut butter and a smooth chocolate frosting. Sweet, nostalgic, and downright delicious!
Video
Equipment
- Jelly-roll pan 17 x 12.25-inch, with sides
- Parchment paper optional
- Stand mixer or hand mixer
Ingredients
- 16 tablespoons unsalted butter 1 cup (or 2 sticks), softened
- 3/4 cup granulated sugar
- 1-1/4 cup brown sugar firmly packed
- 2 large eggs
- 1-1/2 teaspoon vanilla extract
- 1 teaspoon baking soda
- 1 teaspoon salt
- 2 cups old-fashioned oats see note 1
- 1 cup creamy peanut butter see note 2
- 2 cups all-purpose flour
Peanut Butter Filling and Frosting
- 1-1/2 cup creamy peanut butter
- 8 tablespoons unsalted butter 1/2 cup (or 1 stick), softened
- 1/4 cup whole milk
- 1-1/2 teaspoons vanilla extract
- 1/8 teaspoon salt
- 1/4 cup cocoa powder
- 3 cups powdered sugar
Instructions
- Preheat oven to 350°F. Generously grease or add parchment paper to a 17×12.25-inch jelly roll pan (see note 3). Set aside.
- In a bowl attached to a stand mixer (or use a large bowl with a hand mixer), cream together the softened butter (see note 4), granulated sugar, and brown sugar until smooth and creamy (the consistency of peanut butter). Add eggs; beat to combine. Add vanilla, baking soda, salt, and oats. Mix until just incorporated, then add in peanut butter. Mix until just incorporated. Add in flour and mix until just incorporated.
- Spread out dough in an even layer on the prepared sheet pan. Bake for 15–17 minutes and remove. Be careful to not overbake the bars. We want a soft, chewy, and flavorful cookie base!
- Let cookie bars cool for 5 minutes, then warm 1-1/2 cups peanut butter in the microwave for about 30–60 seconds or until it will drizzle nicely. Drizzle the peanut butter evenly on the cookie base and, using a table knife or offset spatula, gently smooth peanut butter in an even layer. Then let the bars cool completely until the peanut butter has fully set up. (I pop the bars in the fridge/freezer for a little!)
- Meanwhile, whip together the frosting. Add all the frosting ingredients to a large bowl (or a stand mixer) and beat until smooth and combined. Dollop scoops of frosting on top of bars and gently spread into an even layer.
- Cut into the bars with a hot sharp knife. Run the knife under hot water, dry it off, and then immediately cut the bars. Enjoy!
Final step! Please let us know how it was by leaving a review.
Recipe Notes
Note 1: Old-fashioned oats and quick oats don’t work the same when baking. Because of their small size, quick oats act more like flour, absorbing more liquid, which results in drier, less-flavorful bars. This recipe uses old-fashioned oats and won’t work the same with other oat types.
Note 2: Make sure to use creamy, not crunchy, peanut butter for best results. I love and highly recommend Skippy® Creamy Peanut Butter (not sponsored), I don’t recommend a natural peanut butter that needs stirring.
Note 3: These bars require a specific-sized pan; unfortunately, the bars won’t turn out well in different sized pans. You are looking for a 17 x 12.25-inch jelly roll pan.
Note 4: The butter should be soft enough to leave a finger indent when using a little bit of pressure, but not soft enough to squish or crush the packaging.
Storage: Cover leftover bars tightly and store at room temperature for up to 5–7 days. To freeze, wrap each bar in plastic wrap and store in a large plastic bag or freezer-safe container for up to 3 months. Thaw bars overnight in the fridge.
Nutrition
Serving: 1serving | Calories: 329kcal | Carbohydrates: 39g | Protein: 6.5g | Fat: 17.3g | Cholesterol: 30.7mg | Sodium: 91.9mg | Fiber: 1.9g | Sugar: 22.7g
Nutrition information is automatically calculated, so should only be used as an approximation.
Do you have any pan suggestions if our oven isn’t wide enough to use the pan you say we need to use for this?
It’s a wall oven, and unfortunately, it simply isn’t very wide. I don’t think this pan size will work.
Yours is one of the best recipes I’ve seen, and looks totally doable as gluten free, but the pan-size stymied me. Or is this recipe specifically only for people with regular-sized ovens?
TY.