Preheat the oven to 425℉. Line a baking sheet pan with parchment paper or aluminum foil.
Remove the carrot tops and scrub the carrots with a vegetable brush. You can roast the carrots with or without the peel.
Place the carrots on the baking sheet pan, drizzle with olive oil and sprinkle with salt and pepper. Using your hands, toss well to make sure the carrots are evenly coated with the oil and spices.
Spread the carrots in a single layer and roast them until tender and lightly browned, about 20 to 35 minutes depending on the size/thickness of each carrot. Remove from the oven and serve.
Follow the recipe instructions to make both the Gremolata and Tahini Sauce. Toss the roasted rainbow carrots with half of the gremolata while the carrots are still warm.
To serve, transfer the carrots to a serving platter and top with the remaining gremolata.
Sprinkle with salt and pepper, then drizzle with tahini sauce. Serve.