Ingredients

1 cup (2 sticks) unsalted butter, softened

1 cup creamy peanut butter

1 cup granulated sugar

1 cup packed light brown sugar

2 large eggs

1 teaspoon pure vanilla extract

2 cups all-purpose flour

1 teaspoon baking soda

½ teaspoon salt

2 cups quick oats

½ cup creamy peanut butter (for frosting)

4 tablespoons unsalted butter, softened (for frosting)

2 teaspoons vanilla extract (for frosting)

3–4 tablespoons milk, as needed (for frosting)

2 cups powdered sugar (for frosting)

Instructions

Step 1: Preheat your oven to 350°F (175°C). Grease a 10×15-inch jelly roll pan or line it with parchment paper to ensure easy removal of the bars.

Step 2: In a large bowl, cream together the softened butter, peanut butter, granulated sugar, and brown sugar until the mixture is smooth and fluffy.

Step 3: Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

Step 4: In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add the dry ingredients to the wet mixture, stirring to combine.

Step 5: Fold in the quick oats until just mixed. Avoid overmixing to keep the bars tender.

Step 6: Spread the batter evenly into the prepared pan. Bake for 20–22 minutes, or until the edges turn golden brown and a toothpick inserted in the center comes out clean.

Step 7: Remove the pan from the oven and allow the bars to cool completely before frosting.

Step 8: To make the frosting, beat together the peanut butter and softened butter until smooth. Mix in the vanilla extract.

Step 9: Gradually add powdered sugar, alternating with milk, until the frosting is light and spreadable.

Step 10: Spread the frosting evenly over the cooled bars. Cut into squares or rectangles and serve.

Tips & Variations

For a crunchier texture, substitute old-fashioned oats for quick oats.

Add chopped peanuts or chocolate chips to the batter for extra flavor and texture.

If you prefer a thinner frosting, add more milk a teaspoon at a time until desired consistency is reached.

Use natural peanut butter for a healthier twist, but note the flavor and texture will differ slightly.

FAQs

Can I use crunchy peanut butter instead of creamy?

Yes, crunchy peanut butter can be used for added texture, but the bars and frosting will have bits of peanuts throughout.

How do I know when the bars are fully baked?

The bars are done when the edges turn golden brown and a toothpick inserted into the center comes out clean or with a few moist crumbs attached. Avoid overbaking to keep them soft and chewy.