The portobello also called portabella is really simply a brown crimini mushroom in disguise. Once the brown crimini grows to be about 4” - 6” in diameter it’s deemed to be a portobello.
Brush Portobellos with olive oil. Place on a baking sheet cap sides up. Roast in a pre-heated 425 degrees oven for about 20 minutes. Season with salt and pepper.Via: Ferry Building Marketplace San Francisco, California
Source: Far West Fungi San Francisco, California