Step 1

In a large skillet over medium heat, heat 1 tablespoon of the olive oil. Add onions, season with salt and pepper, and cook until caramelized, stirring frequently, about 15-20 minutes.

Step 2

Add half of the thyme, cook for one minute, and then add 1/4 cup wine and 1/4 cup beef broth.

Step 3

Cook until liquid has reduced; very little liquid should remain. Remove to a plate or bowl and set aside.

Step 4

To a large bowl, add ground beef, remaining thyme, breadcrumbs, egg, and about 1 teaspoon of salt and 1/2 teaspoon black pepper. Mix together thoroughly with your hands and divide into 16 equal pieces.

Step 5

Take a piece of the meat mixture and flatten into a patty. Add a 1/2 tablespoon of the onions and a cube of cheese to the center of the patty and wrap the meat around the onions and cheese to form a meatball. Repeat with remaining meat.

Step 6

Preheat oven to 375°F.

Step 7

Heat remaining oil in an oven-safe skillet over medium-high heat. Add meatballs and brown on all sides, turning gently.

Step 8

Whisk together 1 3/4 cup beef broth, 1/4 cup wine, and cornstarch and pour over browned meatballs.

Step 9

Place in oven and bake for 15 minutes. Sprinkle remaining cheese evenly over meatballs and return to oven until meatballs are cooked through, about 15 more minutes.

Step 10

To brown cheese, place under broiler for a few minutes. Enjoy!