French Onion Soup with Braised Meatballs

Ingredients

• 1 pound ground beef
• 1 pound ground pork
• ¾ cup heavy cream
• ½ cup grated Parmesan
• ¼ cup panko
• 1 egg
• 2 teaspoons thyme leaves
• 3 ½ teaspoons kosher salt
• 1 teaspoon freshly ground pepper
• Vegetable oil & butter for searing
• 8 tablespoons butter
• 4 onions, thinly sliced
• 1 cup white wine
• 5 garlic cloves, thinly sliced
• 2 tablespoons sherry vinegar
• Kosher salt & pepper
• 2 ½ cups beef broth
• 1 ½ cups coarsely grated Gruyere