Portobello mushrooms are large in size and have a rounded, flat cap that averages fifteen centimeters in diameter and is connected to a thick stem. The smooth cap ranges from dark brown to tan and is firm, thick, and spongy. Underneath the cap, there are dark brown, fleshy gills, a small ring from the cotton-like veil, and the stem is fibrous, white, and dense. When cooked, Portobello mushrooms have a memorable chewy and meaty texture and a smoky, earthy flavor.
