Birria de ternera estilo Aguascalientes
beef for birria (about 2 kg) • whole black peppercorns • dried oregano • bay leaves • small handful cumin seeds • whole cloves • cinnamon (optional) • garlic cloves • tomatoes (about 1 1/4 lbs or 570 grams) • dried chile de árbol peppers (adjust to taste for spiciness) • onions, finely diced • Cilantro, finely chopped •