Serrano Peppers have glossy, smooth, and firm skin. Underneath the thin skin, the flesh is crisp, thick, pale green, and aqueous, encasing a central cavity filled with membranes and small, round, and flat, cream-colored seeds. Fresh Serrano Peppers have a bright, grassy, and acidic flavor followed by a sharp, pungent heat. When cooked, the peppers develop an earthy, smoky flavor with green undertones.