Meatballs are packed with slowly caramelised onions, gruyere, chives, thyme, and garlic, tossed in a rich beef broth and onion sauce, loaded into a garlic butter sub roll with even more gruyere and chives. The ultimate comfort food.
Start by slowly caramelising the onions. Do this over a low heat, adding water if necessary to scrape up anything from the bottom. This should take around 45 minutes.
Divide the caramelised onions in two, saving half for the sauce.
For the meatballs, add half of the caramelised onions, thyme, chives, grated gruyere, an egg, garlic, breadcrumbs, salt, and beef mince to a bowl.
Roll into 9 meatballs, pop onto an oiled baking tray and roast in the oven at 200 C for 20-25 minutes or until cooked through.
To the leftover onions add the flour. Cook over a medium heat, then slowly pour in beef stock. Season with salt and thyme, then add a knob of cold butter to finish.
Add the meatballs and pan juices, toss in the sauce and finish with chives.
Mix the minced garlic with parsley and butter. Spread the garlic butter onto roll, and briefly toast in the oven.
Pack each roll with 3 meatballs, then spoon over some extra sauce. Finish with a mountain of finely grated gruyere, then into the oven just until the cheese has melted. Finish with more chives, and that's it! Eat them while they're warm.