Avocado Quesadillas: Onion Relish

Take a couple of sweet onions, cut them into fine dice, and put them in a bowl. Add some finely minced jalapeño or serrano chile, a handful of finely chopped cilantro, a few leaves of epazote, finely chopped, and salt and pepper. Mix well and squeeze some lime juice over the relish. Taste for seasoning, then refrigerate until needed.