French Onion Mini Meatloaves

Name: French Onion Mini Meatloaves
Ingredients: 2 tablespoons extra-virgin olive oil; 2 large sweet onions, sliced 1/4-inch thick (about 5 to 6 cups); 1 1/2 teaspoons kosher salt, divided; 2 tablespoons, plus 2 teaspoons dry sherry, divided; 3/4 cup panko; 2 large eggs, beaten; 1 (1-ounce) envelope onion soup and dip mix (such as Lipton Recipe Secrets); 2 teaspoons chopped fresh thyme, plus more for garnish; 1 teaspoon black pepper, plus more for garnish; 2 tablespoons Worcestershire sauce, divided; 2 pounds 85/15 ground beef; 8 ounces ground pork; 1/4 cup ketchup; 6 ounces Gruyère cheese, shredded (about 1 1/2 cups); Mashed potatoes, for serving