Preheat the oven to 400F. In a large bowl, stir together the lime juice, olive oil, chili powder, cumin, coriander, salt, sugar, garlic powder and pepper. Stir in the cauliflower and chickpeas. Spread onto a parchment lined baking sheet and roast for 30-35 minutes, until the chickpeas are slightly crispy and the cauliflower is tender. Stir it about every 15 minutes. Remove from the oven and let it cool. In a small bowl stir together the feta, cilantro, lime juice and pepper. Fill the corn tortillas (warm them first) with some of the roasted chickpea and cauliflower mixture, a bit of the shredded cabbage, avocado, jalapeno pepper and a good amount of the feta/cilantro mixture. Serve them warm. Makes 4 servings.