1) Heat the olive oil in a large soup pot. Season the beef shoulder all over with salt and pepper, add it to the pot and brown it. As it's browning, stir in the chilli powder, coriander, cumin, paprika, oregano and cinnamon. Lower the temperature under the meat to toast the spices.
2) In a food processor, puree the onions, garlic, chipotle chillies, jalapenos, tomato puree and sugar, and add it to the pot.
3) Increase the heat to medium to steam the vegetables a little and sweeten the peppers. Add enough water to cover by 2 1/2cm, about 1 litre, and add the tomatoes with their liquid. Bring to the boil and skim off any foam that rises to the surface. Reduce the heat and simmer until the meat is fork-tender and comes apart with no resistance, about 2 hours. As it cooks down, add more water, if necessary.
4) When the beef is done, stir in the masa harina. Take a potato masher and mash the chilli so the meat comes apart in shreds. Season with salt and pepper, to taste.
Garnish each serving with the grated Cheddar, chives and soured cream.