This recipe makes 2 sheet pans of food. Cut it in half for 1 sheet pan only. A lot of my amounts were dictated by what I had around--feel free to adjust to more or less potatoes or cauliflower, just be certain that the ingredients can lay in one layer on the sheet pan and not be overly crowded. I got the idea for this dish from our love for Chaat Masala Roasted Cauliflower.
Preheat the oven to 425 F.
Melt the ghee and then whisk it with the vegetable oil. Use more vegetable oil if your sheet pans are not nonstick. If your pans are not nonstick, brush 1 1/2 teaspoons of the oil-ghee mixture onto each pan.
Brush a little of the oil-ghee mixture onto the chicken skin. Rub with sea salt and a hefty pinch of chaat masala per chicken piece. Remember that the chaat masala has black salt in it, so do not go overboard with the sea salt.
Drizzle half of the remaining oil-ghee mixture over the potatoes in a large bowl and toss them. Sprinkle with a hefty pinch of sea salt and 4-8 teaspoons of the chaat masala.
Spread the chicken pieces (skin side up), potatoes and onion wedges out over the 2 baking sheets. Roll them around a bit to help distribute the oil-ghee.
Bake for 20 minutes.
While the chicken is baking, place the cauliflower florets into the bowl that held the potatoes. Drizzle them with the remaining oil-ghee and toss. Sprinkle with the remaining chaat masala and a hefty pinch or 2 of sea salt.
After the first 20 minutes, add the cauliflower to the baking sheets in the spaces in between the potatoes and chicken.
Return the sheets to the oven, rotating front to back and top to bottom. Roast for another 15-25 minutes, until the chicken registers 160 F and the potatoes and cauliflower are nicely browned.
Serve garnished with cilantro sprigs and lime wedges.