6 pounds lamb necks
Kosher salt and freshly ground black pepper
2 tablespoons olive oil, or more if needed
2 celery stalks, roughly chopped
1 cup roughly chopped peeled carrot
1 cup roughly chopped red onion
1 Fresno chile, halved
½ cup tomato paste
Small bundle of fresh thyme
1 bay leaf
1 head garlic, cloves separated, smashed, and peeled
2 cups dry red wine
⅓ cup red wine vinegar
3 quarts chicken broth, preferably homemade
1 Season the lamb necks with salt and pepper, cover, and refrigerate overnight. Remove from the refrigerator 30 minutes before cooking.
2 Preheat the oven to 325°F.