The serrano pepper (Capsicum annuum) is a type of chili pepper that originated in the mountainous regions of the Mexican states of Puebla and Hidalgo.
Unripe serranos are green, but the colour at maturity varies.
Common colours are green, red, brown, orange, or yellow.
Choose chiles with deep colours, avoiding those that look wrinkled or soft.
When pickled they are known as a sport pepper.
Their flavour is crisp, bright, and biting, notably hotter than the Jalapeño pepper they resemble, and they are typically eaten raw.
Though not as hot as the infamous habañeros, serrano peppers deliver plenty of heat and are the easiest hot chiles to obtain.
These dark green or red peppers are between 1 and 2 inches (2.5–5 cm) in length and about 1/2 inch (1.3cm) in diameter, with a slight taper and a rounded end.
The larger variety, termed the Largo, can be twice this size.
As a general rule of thumb, the smaller the Serrano pepper, the hotter it will taste.
Serrano chiles are extremely hot peppers that range in heat between 5,000 and 20,000 Scoville heat units.