Oxtail Guisado

Preparation

1. Oxtails

   Step 1

   Rinse 2½ lb. ½"–¾" thick oxtails under cool running water; drain and place in a large bowl. Add 1 large red onion, thinly sliced, 1 large green bell pepper, halved, ribs and seeds removed, cut into strips, 1 bunch cilantro, tough stems removed, cut into 2"-long pieces, 6 garlic cloves, finely grated, 2 tsp. sazón con culantro y achiote, 2 Tbsp. adobo seasoning, and 2 Tbsp. dried oregano and mix until meat is coated in seasonings.

   Step 2

   Heat 2 Tbsp. extra-virgin olive oil in a large heavy pot over medium-high. Working in 3–4 batches to avoid overcrowding the pot, add oxtail (try to leave most of seasoning in bowl, but if some cilantro and vegetables adhere, that’s okay). Cook, turning halfway through, until browned on both sides, about 10 minutes. Transfer to a plate as you go.

   Step 3

   Return all oxtails to pot. Pour 4 cups water into bowl with remaining seasonings and vegetables, then add to pot. Bring to a simmer (still over medium-high heat); cover and cook until liquid reduces by a fourth, about 30 minutes.

   Step 4

   Stir 3 oz. tomato paste (about 6 Tbsp.) and a little oxtail cooking liquid in a small bowl until paste is dissolved. Reduce heat to medium and stir tomato paste mixture into broth in pot. Re-cover pot, leaving lid askew, and cook, skimming excess fat or scum from surface as needed and adding up to 1 cup water to keep oxtails covered if needed and/or reducing heat to medium-low to prevent meat from burning underneath, until meat separates from the bones and is tender, 30–60 minutes. (If meat still isn’t tender at this point, add a little more water and continue cooking, checking for doneness and adding a little more water every 15 minutes until ready.)

   Do Ahead: Oxtails can be cooked 3 days ahead. Transfer to an airtight container; cover and chill. Skim off any excess fat before reheating gently on stovetop or in microwave.

2. Salad and Assembly

   Step 5

   Gently toss 2 avocados, cut into about ¾" pieces, 1 large cucumber, peeled, cut into about ¾" pieces, juice of 1 lime, ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt, and a pinch of freshly ground pepper in a large bowl to combine. Taste and season with more salt and pepper if needed.

   Step 6

   Divide oxtails among plates and arrange some salad on the side of each.