I normally leave the turnips in larger pieces, but some of mine had hollow centers I had to cut out. By keeping things in large chunks they don't fall apart and cloud the broth as much.
1.5-2 lbs. bone-in lamb chunks
1 large onion
1 tsp. ground coriander
2-3 tomatoes, peeled and sliced or chopped
2-3 carrots, peeled and cut into thick diagonal slices
3-4 potatoes, peeled and halved
4-5 turnips, peeled and halved
1 handful cilantro leaves, chopped
salt and pepper
In a medium frying pan*, cook the onions in a little oil until they begin to brown on the edges, adding the coriander and some salt. Increase the heat and place the lamb in the pan, searing it on all sides. Transfer the meat and onions to your crockpot.
Cover the meat with about 2" of water (this took ~3 qts. in my cooker). Add the tomatoes, some more salt, and some pepper. Cook on low 4 or more hours while you're at work.
When you get home, increase the temperature to high and add the carrots, potatoes, and turnips so that they cook for another hour or until tender (if your potatoes are very large you may want to put them in for 30 min. before adding the other veggies). While those are cooking, remove the lamb chunks and pull the meat off the bone and return it to the pot (optional). Before serving, adjust the salt level and stir in the cilantro. Serve in large bowls with strips of flatbread to dunk or immerse in the soup.
*If you're using a pressure cooker, you can do this all in the PC. Cook it on the highest pressure for 40 minutes before adding the vegetables. Release the pressure and cook for 7-8 minutes more with the veggies.