Cactus is a common and tasty food item in Mexico and parts of SW USA. Cactus, or NOPALES as they are known in Texas and Mexico, can be found fresh and needle free in the produce section. You can even find jars of Nopales or Nopalitos (little (pieces of) Nopales) in the ethnic aisle of your grocery store. If you choose to use those please drain them and rinse them well. Green Beans or chayote can be substituted if cactus is not available. The nutritional info here is not correct as the olive oil is used for coating the items you are grilling and in the dressing. Not all of it is consumed. This recipe is from La Comida Del Barrio (meaning Foods from the neighborhood) Latin American Cooking in the U.S., by Aaron Sanchez (Clarkson Potter, 2003) This dish would be wonderful with any Mexican cerveza (beer) or with a crisp and fruity Sauvignon Blanc.