• Bring the vinegar to a simmer in a small pan over low heat. Remove from the heat; toss in the onion, sumac, and salt. Put in a container, cool, cover, and refrigerate.

=====grilled cauliflower=====

• Whisk the oil, salt, turmeric, coriander, and cumin seeds together in a medium-sized bowl. Add the cauliflower upside down, holding by the stem. Turn to coat. Leave the cauliflower to marinate for one hour at room temperature. Turn as necessary until thoroughly coated. While the cauliflower is marinating, make the sauces.

=====tahini sauce=====

• Combine all of the ingredients in a blender. Blend until smooth, about 1 minute. Remove to a container and refrigerate until needed.

=====herb sauce=====

• Place the herbs, peppers, cumin, garlic, and Kosher salt in a food processor fitted with a metal blade. Pulse until chopped and combined. With the food processor running, slowly pour in the olive oil. Remove to a container; set aside until ready to use. Refrigerate extra sauce.
• If you're using a charcoal grill, start the coals after the cauliflower marinates for 30 minutes. Set the grill up for indirect heat. If you're using gas, set the grill up for indirect cooking and preheat the grill.
• Place the cauliflower on an oiled grill pan; reserve the marinade. Grill the cauliflower indirectly, grill closed, for one hour and 15 minutes, or until the cauliflower is tender. (This may take longer depending on the size of your cauliflower and the heat of your grill.) Baste the cauliflower generously with the marinade every 15 minutes while cooking. The surface of the cauliflower will be caked with spices. (You can also bake the cauliflower in a 375°F oven for the same amount of time with the same directions.)
• Serve the cauliflower on a serving platter. Drizzle with 1/2 cup of the tahini sauce and 1/2 cup of the herb sauce. Sprinkle lightly with Maldon sea salt. Serve the remaining sauces on the side.