In a large pot with a lid, combine the pork, marjoram, thyme, bay leaf, ½ teaspoon salt, and enough water to cover the meat. Bring to a boil, then reduce to a simmer and cook for 1-2 hours, until the meat is very tender.
Place a steamer basket in a large saucepan with 1 inch of water. Add the potatoes, cover, and steam over medium-high heat until fork-tender, about 10-15 minutes. Drain.
In a separate saucepan, heat the oil on high until one line of smoke appears.
Add the chorizo and cook until lightly browned and fragrant.
Add the garlic and onions and cook until fragrant.
Add the puréed tomatoes and chipotle, chickpeas, salt, sugar, braised pork, braising liquid and steamed potatoes.
Bring to a simmer and cook for 30 minutes, or until desired flavor is achieved.
Combine the crema ingredients in a bowl.
To serve, divide the stew between bowls. Top with diced onions, marjoram and lime cotija crema. Serve with tortillas on the side.