Peanut Butter and Oat Brownies

Ingredients

• 3/4 cup butter, softened
• 3/4 cup peanut butter
• 3/4 cup white sugar
• 3/4 cup brown sugar
• 1 1/2 cups all-purpose flour
• 1 1/2 cups rolled oats
• 1 1/2 teaspoons vanilla extract
• 2 eggs
• 2 teaspoons salt
• 1/2 cup peanut butter, or as needed