It's all about layering flavors in this colorful company-worthy salad: a garlicky sumac yogurt sauce is spread on the plate, then topped with chewy sorghum, roasted carrots, blanched dandelion greens, and delicate celery leaves.
Preheat oven to 400 degrees. Toss carrots, garlic, bay leaf, and thyme with oil on a rimmed baking sheet. Season with kosher salt and pepper. Roast, turning carrots occasionally, until tender and caramelized, 35 to 40 minutes. Remove from oven; let cool slightly.
Meanwhile, prepare an ice-water bath. Bring a medium pot of salted water to a boil. Add greens and cook until bright green and just tender, 1 minute. Transfer to ice-water bath; drain.
Remove garlic skins and mash cloves in a bowl. Whisk in yogurt and sumac. Season with salt and pepper. Let stand until sumac has started to tint yogurt, about 30 minutes.
Spread yogurt mixture on a serving platter. Top with sorghum, greens, and carrots. Drizzle with oil and season with flaky salt and pepper. Sprinkle with celery leaves. Serve immediately.