They're most often made with peanuts (garrapiñadas de maní) although you can easily make them with other nuts, such as almonds (garrapiñadas de almendras).
Here's how you make them:
250g unsalted peanuts
200ml cold water
|Garrapiñadas in a cone, sold on the street in Buenos Aires|
Empty out the peanuts into a dry, non-stick saucepan and place over a gentle heat, just to warm them through. Combine the water and sugar in a jug and, as soon as the peanuts start to brown slightly on the outside (keep an eye on them) pour the sugary mixture into the pan. Give the contents a stir and then leave to bubble for about five minutes. The caramel will begin to darken and thicken - when it turns golden, tip them out onto a plate lined with greaseproof paper. As they cool, they'll stick together and turn brittle, so crack them up a bit with a spoon before they all set together completely. Eat once cool.