A jalapeño is a medium-sized chili pepper, usually two to three inches long, that adds a spicy kick to food. Named after Xalapa, a city in Mexico, jalapeños are popular in Mexican and Tex-Mex cooking, showing up in everything from tacos and nachos to salsas and guacamole.

The heat level of jalapeños varies quite a bit. Some are fairly mild, giving just a gentle tingle on your tongue, while others pack serious heat that might make your eyes water. The spiciness comes from a chemical called capsaicin, which affects your pain receptors and makes it feel like your mouth is burning (even though it isn't).

You'll often see jalapeños sliced into rings and scattered on pizza or mixed into cream cheese for jalapeño poppers. When dried and smoked, jalapeños become chipotles, which have a deeper, smokier flavor. The seeds and white membranes inside hold most of the heat, so removing them can make the pepper milder.

Many people who initially find jalapeños too spicy gradually build up a tolerance and come to love the bright, fresh flavor they add to food.