Ají amarillo paste
In Lima's markets ají amarillo is sold fresh all year, and most Peruvian cooks keep a tub of this paste in the fridge the way others keep tomato purée: it is the golden base of causa limeña, ají de gallina, papa a la huancaína, chupe and the sauce for tiraditos. The chillies are seeded, de-veined and blanched in three changes of water, which tames the heat and the raw grassiness, then peeled and blended with oil into a thick, silky, saffron-orange paste. It tastes fruity and sunny, almost like apricot and passion fruit, with a rounded, medium heat. Abroad, buy whole frozen ají amarillo from Latin grocers; dried ají mirasol, soaked, gives a darker, earthier paste. Common mistake: skipping the peeling; the thin skins leave papery flecks and a bitter edge. It is ready when it is completely smooth and holds a soft peak like thick hummus. This is a low-acid paste: keep it in the fridge for a week or freeze it, never on the shelf. Chef's tip: freeze it in an ice-cube tray; one cube is about a tablespoon, just right for a pot of ají de gallina.

















