Toast the peanuts in a dry skillet over medium-low heat for 4–6 minutes, stirring until lightly golden. Transfer to a plate and reserve 10 g for serving. Briefly toast the cleaned ancho chiles separately, then soak in hot water for 15 minutes and drain.

Roast the tomatoes and onion on the skillet or griddle for 12–15 minutes, turning until softened and spotted with brown. Add the garlic near the end so it softens without burning. Retain tomato juices.

Blend the peanuts except the reserved garnish with the chiles, roasted vegetables and juices, cinnamon, cumin and 500 ml of the water until no hard pieces remain. Work in batches if needed and cool hot ingredients first unless your blender allows them.

Pat the chicken dry without rinsing and season with 3 g salt. Heat the oil in the wide pot and brown the thighs 3–4 minutes per side. They will not yet be cooked through. Move them to a clean plate.

Carefully add the blended sauce to the same pot and cook 5 minutes over medium-low heat, stirring along the bottom. Add the remaining 200 ml water and return the chicken with its juices.

Partially cover and simmer gently for 20–25 minutes, stirring carefully. Add hot water a little at a time if the sauce becomes pasty. Check that the thickest part of every piece reaches at least 165°F.

Taste and add up to the remaining 3 g salt if needed. Divide among six plates, spoon over the sauce and scatter on the reserved peanuts. The sauce should coat the chicken and slide from a tilted spoon.