Heat your oven to 450ºF and drizzle a large sheet pan with olive oil. Cut the cabbage into eight wedges and transfer to the sheet pan. Drizzle the cabbage with a few tablespoons of oil and season with salt and pepper. Roast the cabbage for 20 to 30 minutes or until golden and lightly charred and frizzled.
Meanwhile, make the dressing. Whisk together the tahini, lemon zest, lemon juice, minced garlic, Dijon mustard, and red wine vinegar in a large bowl. Add in 2 tablespoons of oil and 2 tablespoons of water, and the cheese, and season with salt and pepper. If needed, add more oil and/or water a tablespoon at a time to reach a thick and saucy consistency.
To serve, spread the tahini dressing down onto a serving platter. Top with the cabbage and serve with extra Parmigiano Reggiano and pepper.
