Grilled Shrimp without beer ketchup

1 medium red onion, cut into 1/4-inch-thick slices Cooking spray 3 cups diced peeled mango 2 1/4 teaspoons salt, divided 2 cups chopped seeded tomato 1/3 cup[...]

24 large shrimp, peeled and deveined (about 1 1/2 pounds) 1/2 teaspoon garlic powder 1/2 teaspoon ground cumin 1/4 teaspoon kosher salt Black bean salsa: 1/4[...]