Serranos Peppers - literally meaning from the highland or mountain (where they are believed to have originated), these are the traditional Mexican HOT pepper. Serrano Pepper Characteristics- Long, conical shape, with tapering rounded end, length is 2-5 cm (1-2 inches) long, just under 1.25 cm (1 - 2 inch) wide. Bright dark green, with no blemishes, thick firm skin. Its thick flesh and spicy seeds leave you with a clean-biting, pleasantly spicy taste. Most common uses are in salsa, sauces, guacamole, or anything that needs to be spiced up .