Perfect Summer Basil Burger

Name: Perfect Summer Basil Burger
Ingredients: 1 1/4 pounds ground beef (80-percent lean); Kosher salt and freshly ground black pepper; 1 tablespoon vegetable oil; 1/4 cup shredded mozzarella; 4 English muffins, halved horizontally and toasted; 1 tomato, sliced and lightly salted; Perfect Basil Sauce, recipe follows; 2 tablespoons grated Parmesan; 1 green onion, chopped; 3 tablespoons roughly chopped fresh basil; 1 large clove garlic, minced; 1/2 cup prepared mayonnaise; 3 tablespoons sour cream; 1/2 teaspoon Worcestershire sauce