The magnificent portobello, in all its glory, is dressed to the nines in this dish, and no vegetable deserves it more. The mighty meaty mushroom is basted with a sauce that combines the chile heat of gochujang and the sweetness of teriyaki and grilled to perfection. Served with a bright lime slaw and onions caramelized in the same to-die-for sauce, portobellos have never looked so good.
Bring a small pot with rice and 1 ½ cups water to a boil. Reduce to a simmer, cover, and cook until rice is tender, 18-20 minutes. Remove from burner and set aside, covered. While rice cooks, prepare ingredients.
Prepare the Ingredients
Using a spoon, scoop out black undersides (gills) of portobello mushrooms and remove stems. Peel onion and slice into ¼” rounds. Halve lime and juice.
Make the Sauces
To make basting sauce, combine gochujang, 2 tsp. olive oil, and teriyaki glaze in a small bowl. Transfer 2 Tbsp. basting sauce to another small bowl and mix with mayonnaise to make finishing sauce.
Grill the Mushrooms and Onions
Heat an outdoor grill or grill pan to medium-high heat and lightly coat with cooking spray. Lightly brush onions and mushrooms with olive oil. Working in batches, grill onions and mushrooms until browned and soft, 3-5 minutes per side. Return cooked vegetables to grill, brush with basting sauce, and continue to grill until sauce caramelizes and chars on vegetables, 2-3 minutes per side. Basting sauce is spicy. Use to taste. Transfer to a cutting board and cut mushrooms into eight wedges each.
Make the Slaw
Combine red cabbage, matchstick carrots, 2 tsp. lime juice, 2 tsp. olive oil, ¼ tsp. salt, and ¼ tsp. pepper in a medium mixing bowl.
Plate the Dish
Spoon rice into a bowl and top with grilled vegetables and slaw. Drizzle with finishing sauce and serve on the side, if desired.