Xispa means spark
It's Catalan, and it's what jumps off the griddle when a thick patty lands on it at 300 degrees. We sear it hard on both sides, leave it juicy in the middle, and put the cheese on while it's still on the heat.
That's the whole idea. Two friends, one griddle, five burgers, and a queue on Carrer de la Xispa most nights.