If you went to school in America anytime between the 1970s and the 1990s, there is a good chance you remember these. Not by this name necessarily, and maybe not this exact recipe, but from a cafeteria tray slid across a lunch counter by someone in a hairnet who knew exactly what she was doing. Lunch Lady Peanut Butter Bars are one of those nostalgic school lunch legends that people remember long after their school days have ended. A soft and chewy peanut butter base topped with a sweet chocolate frosting, it’s a simple combination that’s so easy to love — even if you’re nowhere near a school cafeteria.

What Ingredients Do You Need for Lunch Lady Peanut Butter Bars?

Mostly pantry ingredients! You’ll need:

• Butter.
• Creamy peanut butter. (And plenty of it!)
• Brown sugar, white sugar, and powdered sugar.
• Eggs.
• All-purpose flour.
• Baking powder.
• Cocoa powder.
• Milk.
• And vanilla extract.

Why is it so important not to overbake these?
The magic of a great peanut butter bar such as these is in the texture. It’s soft and almost fudgy, but a little crumbly too. Overbaking runs the risk of making them tough, so pull them out when the edges are just golden and the center has barely set, even if they look like they could use another few minutes. They’ll firm up as they cool, and that slightly underbaked center is exactly what makes them so irresistible. Trust the timer and step away from the oven!

How Do You Make Lunch Lady Peanut Butter Bars?

These come together quickly and easily with just one bowl, which means cleanup is minimal and the bars are ready before you know it. (Great news!) The frosting goes on while the bars are still slightly warm so it spreads like a dream and sets into that perfect fudgy layer.
Here’s how it all comes together:

Beat the butter, both sugars, and peanut butter together until light and creamy, then add the eggs and
vanilla and mix until combined. Stir in the flour, baking powder, and salt until just combined — but don’t overmix — then press the dough out evenly into your greased half sheet pan with a spatula. Bake for about 15 minutes until the edges are just golden and the center has barely set, then pull them out and let them start to cool.

While the bars cool, beat together the butter, powdered sugar, cocoa powder, milk, and vanilla until you have a smooth, glossy chocolate frosting. Spread it generously and evenly over the bars, all the way to the edges. Let everything set completely before cutting into squares, though if you sneak a corner piece while it’s still warm, nobody will know.