Peanut Butter Lunch Lady Bars

Sheet pan cookies are a total lifesaver—quick to make and ideal when you need a dessert that feeds a crowd without extra work. Inspired by that legendary lunch lady who always knew how to keep everyone satisfied, these Peanut Butter Cookie Bars deliver big flavor with simple effort. And don’t worry—these are miles better than anything you’d find in a cafeteria!
Ditch the Store-Bought Desserts
If dessert usually means a rushed trip to the store, these homemade cookie bars are about to change your routine. While packaged sweets are convenient, nothing beats the ease and flavor of baking your own. Cookie bars are endlessly versatile, whether you’re craving chocolate or something rich and nutty. Lately, peanut butter has stolen the spotlight—and for good reason. Every bite is pure comfort.
The Ultimate Peanut Butter Frosting
Peanut butter lovers, this one’s for you. These bars are finished with a smooth, indulgent peanut butter frosting that truly makes them shine. Prefer a twist? A rich chocolate frosting works beautifully too. Peanut butter desserts are all about that perfect balance of sweet and salty, and these cookie bars nail it every time.
Ingredients
| Ingredient | Amount |
|---|---|
| All-purpose flour | 2 cups |
| Granulated sugar | 2 cups |
| Large eggs, beaten | 2 |
| Creamy peanut butter | 1½ cups, divided |
| Unsalted butter, softened | 1½ cups (3 sticks) |
| Milk | ½ cup + 2 tablespoons, divided |
| Baking soda | 1 teaspoon |
| Vanilla extract | 1 teaspoon |
| Salt | 1 teaspoon |
| Powdered sugar | 4 cups |
Preparation
- Preheat the oven to 400°F. Grease a large cookie sheet or line it with parchment paper.
- In a large bowl, mix together the flour, sugar, baking soda, and salt. Set aside.
- In a separate bowl, whisk together ½ cup of milk, vanilla extract, and beaten eggs. Set aside.
- In a saucepan over medium heat, melt 1 cup of butter with 1 cup of peanut butter, stirring until smooth. Remove from heat.
- Gradually stir in the dry ingredients, followed by the milk and egg mixture, mixing until fully combined.
- Spread the batter evenly onto the prepared cookie sheet. Bake for about 20 minutes, or until a toothpick inserted in the center comes out clean. Let cool completely before frosting.
Frosting
- In a saucepan, bring 1 stick of butter and ½ cup peanut butter to a boil.
- Stir in 2 tablespoons milk, then gradually mix in the powdered sugar until smooth.
- Pour the frosting over the cooled bars, spreading evenly. Allow it to set before slicing and serving.




