French Onion Chicken Meatballs

Ingredients

• 2 tablespoons extra virgin olive oil
• 1 pound ground chicken
• 1/2 cup Gruyère cheese or Swiss cheese
• 1/4 cup breadcrumbs
• 2 tablespoons parsley, chopped
• 1 large egg, beaten
• 2 cloves garlic, minced
• 1 teaspoon kosher salt
• ground black pepper, to taste
• 4 tablespoons butter
• 2 large onions, thinly sliced
• 2 cups low-sodium beef broth
• 2 teaspoons thyme, chopped, plus more, to taste, for garnish
• kosher salt, to taste
• 1 1/2 cups Gruyère cheese or Swiss cheese