Dry the pork neck and sprinkle it with salt. Make small cuts in the meat and stick the slices of garlic in it.
In a bowl, mix the mustard, honey, soy sauce, olive oil and spices. Stir everything into a thick mixture, smear the meat with it. Cover with plastic wrap and leave to marinate for 12 hours in the fridge.
It's best to leave it to marinate overnight.
Put the marinated meat in a tray. Pour on the remaining marinade on top, if any. Put the rosemary and thyme leaves in the tray. Pour in the wine and cover the tray with aluminum foil.
Bake in a preheated 320°F (160 °C) oven about 3 hours. Next, remove the foil and arrange the cleaned, seasoned with black pepper and salt sweet potatoes and red onions around the meat.
Bake the dish until the meat gains a crunchy crust and sweet potatoes soften.