Juicy Lucy Burger (a.k.a. Jucy Lucy)

Ingredients

• 4 slices American cheese (about 3 ounces)
• 1 1/2 pounds ground chuck (15 to 20 percent fat content), chilled
• 1 1/4 teaspoons kosher salt
• 1/2 teaspoon garlic powder
• 1/2 teaspoon Worcestershire sauce
• 1/4 teaspoon freshly ground black pepper
• Vegetable oil, for oiling the grill
• 4 (4-inch) hamburger buns, split and toasted
• Sliced pickles, for serving