1) Cut the nopales in dice or short strips, then cook in boiling water with onion strips and a bit of salt. Drain the vegetables in a strainer once cooked; leaving them in the strainer until they have cooled down.

2) Using your blender, liquefy the coarsely chopped chipotles with the also coarsely chopped tomatoes. Carefully check the spiciness of your tomato sauce and add more chipotles if you like spicier...

3) Heat up some oil in a pan, pour the liquefied tomatoes with chipotle and cook the sauce for 5 minutes, bringing it to a boil first then reducing heat setting to a simmer.

4) Grease an ovenproof dish with oil and in it, arrange a layer of cactus, tomato and chile sauce, then a layer of cream to finish with some grated cheese on top. Preheat the oven to 350 ˚F.

5) Place in the oven, which should be already at the 350 ˚F, and leave it about twenty-five minutes before serving, or until the cheese on top has formed a nice crust... do not burn!

Serve with hot tortillas or over tostadas.