To mitigate cauliflower's blandness, serve with plenty of the same simple, tasty gravy used to baste it while it bakes. In its favor, other than the handsome appearance of the cauliflower, is ease of preparation.
For the cauliflower: Cut away the fibrous green leaves and any woody part of stem. Put in a casserole dish that will hold it comfortably, stem end down. Cover with foil.
Bake for 30 minutes, covered, then remove from the oven.
For the gravy: Combine the broth and soy sauce in a small saucepan and bring to a simmer. Stir in the seasoning blend and add a few grinds of pepper.
Combine the arrowroot cornstarch with just enough water to dissolve in a cup or small container. When the broth mixture is at a steady simmer, slowly whisk in the cornstarch, stirring constantly until the liquid is thickened.
Remove from the heat and whisk in the optional nutritional yeast.
Using oven mitts or a clean tea towel, uncover the cauliflower, and transfer to a plate for the moment. Drain off any water remaining in the casserole dish and use the same piece of foil to cover the bottom of the dish.
Using a spoon and/or a basting brush, cover the surface of the cauliflower with a nice layer of the gravy. Set the remaining gravy aside.
Bake the cauliflower uncovered for 15 to 20 minutes longer (depending on the size and density of the cauliflower), or until you can pierce through the center fairly easily. Don’t let it get overdone and mushy, though!
Before serving, coat the cauliflower with another layer of gravy, then transfer it to a serving platter lined with greens of your choice.
Transfer the remaining gravy from the saucepan to a small serving container. Serve the cauliflower at once, cutting it into 8 or so equal wedges, and pass around the gravy.