Rice or grate the cauliflower. I use the grating attachment on my food processor or you could grate by hand, but it’s a pain in the butt. Save 1-1/2 cups for this recipe and the rest for something else. It’s tasty fried up in this side dish.
In a large bowl, mix the beef, pork, garlic powder, salt and pepper.
Put a large pot of water on the stove over high heat. To prepare the cabbage for rolling, you’ll lightly boil it whole and peel the leaves off a few at a time. Cut the core out of the cabbage and place in the pot. Bring to a boil and then reduce the heat to a simmer. As the leaves soften, you can peel them off with a spoon. Take care not to rip them in half. The whole process usually takes about 15 minutes. Alternatively, you can throw the whole cabbage in and let it simmer for about 15 minutes. The outermost leaves will become very soft but still usable. In either case, peel as many of the leaves off as you can and let cool a bit.
In a large skillet over medium-high heat, add a tablespoon of coconut oil or your fat of choice. Add the onion and grated cauliflower and sauté for 3 to 5 minutes until the onion is translucent and the cauliflower is softened. Turn off the heat and allow to cool for 5 minutes.
Combine the onion and cauliflower with the meat, and mix by hand to incorporate all the ingredients.
Roll the golumbki by holding a cabbage leaf, concave side up with the stem toward you, and placing a large spoonful of the meat mixture at the stem end. Then roll forward, fold the sides in and end with the seam down.
Mix the crushed tomatoes and tomato sauce in a bowl. Put ~1 cup in the bottom of the slow cooker (or casserole dish). Lay the golumbki in with the seam side down. Cover with the remaining tomato mixture once the slow cooker is full.
For a slow cookers, cook on low for 5 hours. If using the oven, cover the top of the dish with foil and bake for 60-90 minutes at 350°F.