Vegetarians and meat-eaters alike will appreciate the appeal of this hearty knife-and-fork dish.
Preheat oven to 425 degrees. Trim bottom of stem from cauliflower and stand head upright on a cutting board. Cut into 4 vertical slices, each 1 to 1 1/2 inches thick. Arrange in a single layer on a rimmed baking sheet and brush both sides with oil. Season with salt and pepper.
Roast, flipping once, until cauliflower is tender and golden, about 35 minutes. Serve with romesco sauce and topped with herbs or microgreens.