1. Put the beans and 4 cups of water in a pressure cooker. Close the lid and bring to high pressure over high heat. Reduce the heat to low or just enough to maintain pressure and cook for 5 minutes. Remove from the heat; let stand for 10 minutes, then carefully release the steam valve and drain. The beans should be barely tender with a hard core.
2. Meanwhile, in a medium bowl, soak the guajillo and chipotle chiles in the 4 cups of very hot water until softened, 15 minutes. Drain, reserving 1/4 cup of the liquid. Transfer the chiles and the reserved liquid to a blender and add the garlic, onion, cumin, oregano and coriander. Blend until fairly smooth. Add the tomatoes and their juices and puree until smooth. Strain into a bowl through a fine sieve, pressing hard on the solids.
3. Wipe out the pressure cooker. Add the olive oil and heat until shimmering. Season the pork with salt and pepper and add half of it to the pot. Cook over moderately high heat until browned all over, about 10 minutes. Using a slotted spoon, transfer the meat to a plate. Brown the remaining meat. Return all of the meat to the pot and add the tomato puree, stock, bay leaves and drained beans. Close the lid and bring to high pressure over high heat. Reduce the heat to low or just enough to maintain high pressure and cook for 30 minutes.
4. Remove the pressure cooker from the heat and let stand for 10 minutes, then carefully release the steam valve. Add the hominy and cook uncovered over moderately high heat for 5 minutes. Discard the bay leaves. Season with salt and pepper and serve with rice, sour cream, cilantro and cheese.