Jalapeños are small Earth chile peppers distinguished for their "heat" or extreme spiciness when eaten. Cooks often used jalapeños as an ingredient in some dishes or as a garnish.
Jalapeño peppers were a main ingredient in Rodeo Red's Red-Hot, Rootin'-Tootin' Chili. When Neelix made such a chili on USS Voyager in 2374, he used a few too many and some crewmembers experienced heartburn and had to visit sickbay. The proper pronunciation of jalapeños is "ha-luh-PANE-yo". Neelix however pronounced it "jal-ap-anos". (VOY: "Message in a Bottle")