4 bone-in beef shanks (approx. 2.5 lbs / 1.1 kg total, about 1.5 inches thick)
2 tbsp olive oil (for searing)
1 large yellow onion, diced
2 medium carrots, chopped into 1/2-inch pieces
2 stalks celery, chopped into 1/2-inch pieces
4 cloves garlic, minced
2 tbsp tomato paste
1 cup (240ml) dry red wine (e.g., Cabernet Sauvignon or Pinot Noir)
2 cups (480ml) low-sodium beef broth
2 sprigs fresh rosemary (or 1 tsp dried)
4 sprigs fresh thyme (or 1 tsp dried)
2 bay leaves
1 tsp sea salt
1/2 tsp freshly ground black pepper