Blueberry Swirl Peanut Butter Blondies - Blueberries

Ingredients

• 4 ounces fresh blueberries
• 2 tablespoons lemon juice (half a lemon)
• 1 tablespoon lemon zest
• 1 teaspoon vanilla extract
• 1/4 cup granulated sugar
• 1/8 teaspoon salt
• 1 teaspoon cornstarch mixed with 1 tablespoon water
• 8 tablespoons unsalted butter
• ¾ cup creamy peanut butter
• 1 cup dark brown sugar, lightly packed
• 2 large eggs
• 1 teaspoon of vanilla
• 1/2 teaspoon baking powder
• 1 ¼ teaspoon kosher salt
• ½ cup all-purpose flour
• Sesame seeds (optional)