1. In a medium bowl, cover the beans with at least four cups cold water. Cover with a kitchen towel and soak on the counter for eight hours or refrigerate for 12 hours. (You can also use the quick-soak method; see below.)
2. Preheat the oven to 200 degrees Fahrenheit. Pour the oil in a large (at least eight-quart) heavy pot with a lid, sprinkle half a teaspoon of the salt over the oil, and arrange the onion slices to cover the bottom of the pot, in a few layers if needed, to fit. Flip the onion slices so that both sides are coated in the salted oil. Scatter the wheat berries and soaked beans on top of the onions. Trim the cauliflower so that most of the stem is removed and you can stand the cauliflower upright without it tipping over, then arrange the cauliflower on top of the beans and wheat berries. Nestle the sweet potato halves and whole tomatoes around the cauliflower. Scatter the garlic cloves around the pot.
3. In a large bowl, whisk together the broth, water, tomato paste, cumin, sweet and smoked paprikas, cayenne, and the remaining 4 teaspoons salt. Pour the liquid into the pot; it should come up to the top of the sweet potatoes, and the cauliflower head should stick out the top. Bring the pot to a boil, then cover it tightly (if your pot doesn’t have a tight seal, seal it with foil first). Transfer the pot to the oven and cook until the beans and wheat berries are tender, the cauliflower is scoopable with a spoon, and the tomatoes are shriveled, eight to 10 hours. Uncover, season with salt to taste and serve with Schug-a-Churri (recipe follows), chopped salad (recipe follows), and tahini sauce.
Tips: Soaked beans can be drained, rinsed, and frozen, then used from their frozen state in recipes calling for soaked beans. Just make sure you mark freezer bags with the original amount of beans, pre-soaking, to avoid confusion when you’re ready to use them.
Quick-Soaked Beans:
This shortcut allows you to skip the soaking step and achieve beans almost as perfect as the ones that soak in the fridge overnight. Place the beans in a medium saucepan, cover with four inches of cold water, bring to a boil, and boil for five minutes. Remove the pan from the heat and let the beans cool in their water for one hour. Drain the beans and proceed with the recipe.