Bushs Baked Beans Sloppy Joe Sliders

Name: Bush’s Baked Beans Sloppy Joe Sliders
Ingredients: 1 medium yellow onion; 1 large red bell pepper; 3 tablespoons unsalted butter, divided; 12 ounces lean ground beef; 1 1/2 teaspoons garlic powder; 1 teaspoon kosher salt; 1/2 teaspoon freshly ground black pepper; 1/4 cup tomato paste; 1 (28-ounce) can Bush's Baked Beans; 2 teaspoons Worcestershire sauce; 2 (12-ounce) packages Hawaiian sweet rolls, such as King’s; 2 teaspoons white sesame seeds