Sancocho with tomato aji sauce

Ingredients:

For the soup:

• 900 g of beef ribs, sliced ​​crosswise
• 900 g chicken thighs (remove skin and excess fat)
• 3 tbsp. l. olive oil
• 2 large onions, finely chopped
• 3 crushed cloves of garlic
• 2 large tomatoes, cored, peeled, seeded and chopped
• 3 bay leaves
• 1 tbsp finely chopped fresh thyme leaves
• 2 green plantains, peeled and cut into 5cm long pieces
• 2 ripe plantains, peeled and cut into 5cm long pieces
• 1 large bunch fresh cilantro (stems tied with kitchen string)
• 14 cups homemade or canned chicken broth
• 700 g peeled small red or yellow potatoes
• 3 cups diced pumpkin or butternut squash
• 10 long (5 cm) pieces of frozen cassava root
• 4 ears of corn, peeled and quartered
• White rice for serving (optional)
• 1 medium avocado, halved, skinned, seeded and sliced ​​for serving (optional)
• Arepas or tortillas for serving (optional)

For the aji sauce:

• 1 small plum tomato, cored and finely chopped (optional)
• 1/2 small Scotch bonnet or habanero pepper, seeded and finely chopped
• 1 cup finely chopped fresh cilantro leaves
• 8 finely chopped green onions (white and light green parts only)
• 1 tbsp finely chopped white onion
• 2 tsp fresh lime juice (from about 1/2 a lime)
• 3/4 cup water
• Salt

Preparation:

1. For adji: In a small glass bowl or jar with a tight-fitting lid, place the cilantro, green onions, chili pepper, and onion, along with lime juice and 3/4 cup water. Add the tomato (if using), season with salt to taste, and combine all ingredients. Close the lid and let the aji sit at room temperature for a few hours to allow the flavor to infuse, then refrigerate until serving.
2. For the soup: Heat the oil in a large saucepan over medium heat for 1 minute. Add the onion and garlic and cook until soft and translucent, stirring occasionally, about 5 minutes. Add the tomatoes, bay leaves, and thyme and continue cooking for another 5 minutes.
   
   Add the chicken and beef ribs and cook until the tomatoes are tender, about 15 minutes, stirring occasionally and skimming off any foam from the surface of the broth as needed. Add the green plantains, cilantro, and chicken broth and bring to a boil. Reduce the heat to medium-low and simmer, covered, until the plantains are tender, about 30 minutes.
3. Using a slotted spoon, remove the chicken from the pot. Add the potatoes, pumpkin, ripe plantains, cassava, and corn and simmer, uncovered, until the vegetables are tender, about 20 minutes. Remove the cilantro and bay leaves, return the chicken to the pot, and reheat.
   
   To serve, arrange chicken pieces, some beef, plantains, and a few pieces of cassava and potato on each plate. Serve the broth in a small bowl, the aji sauce in a separate bowl, along with rice, corn, a little avocado, and arepas and tortillas on a separate plate.