Gently toss the celery root, squash, and mushrooms with olive oil, salt and pepper. Separately, toss plum tomatoes with salt and pepper, thyme, lemon zest, and coriander seed. Arrange all vegetables in their separate zones on a parchment-lined baking sheet. The oyster mushrooms will cook fastest, followed by the squash, then the celery root, tomatoes, and garlic. I remove them as each is perfectly tender and continue cooking the rest.