In a large 6-7 quart slow cooker sprinkle the onions on the bottom and place the pork shoulder on top of them.
Then layer the ingredients as noted in the ingredient list: garlic, green chilies, white and yellow hominy, cumin, jalapeno slices, enchilada sauce and chicken broth. Cook on HIGH for 7 hours or until the meat is fully cooked.
Remove the pork onto a plate or cutting board. Using two forks, shred the meat, discarding any pieces of fat, and return the pork to the slow cooker.
Serve with garnishes. Note: the posole may be removed from the slow cooker, placed into a sealed container (allow to cool first) and refrigerated to allow flavors to deepen further before serving.
Though this version uses mild enchilada sauce it is still spicy. I suggest adding hot sauce when serving if more heat is desired versus using hot enchilada sauce which risks it becoming too spicy for some diners.