Turkey Burger with Grilled Onions

1 (20-ounce) package ground turkey with white meat 4 cloves garlic, minced 2 teaspoons Worcestershire sauce 2 teaspoons olive oil 1 teaspoon smoked paprika ¼ teaspoon ground cumin 8 ounces thinly sliced onions crumbed blue cheese, or multi-cheese crumbles packages4 hamburger buns