Prep time: 60 minutes
Heat oil over medium heat in a dutch oven or stew pot. Add the thawed meat. Sear on each side of each cube for about 2 minutes, or until dark brown on all sides. Remove meat from pot and set aside. Add diced onion to the cooking juices from the meat in the pot. Sauté until softened and slightly translucent. Add the potatoes to cook slightly while slicing the cabbage.
Cut the half head of cabbage in half again, then slice both quarters to ¼ inch ribbons. Rinse thoroughly under running water, as cabbage tends to hold onto dirt in its crevices. Set aside to dry out, then wash the collard greens. If desired, you may de-stem the leaves with a sharp knife, but the stems will cook down in the stew and lose their fibrousness. Stack the leaves together. Starting on a long edge, roll the leaves into a tight spiral. Use a sharp knife to cut the leaves into ¼ inch ribbons.Add the cabbage, mushrooms and collards to the pot, then add the stock and stout. Bring the whole thing to a boil, then reduce heat to a simmer. Allow to simmer away for 40 minutes to an hour, until meat is tender and potatoes are soft. Feel free to add more broth to create a more soupy consistency. Add salt and pepper to taste, and serve with warm slices of soda bread topped with butter.