Step 1

Put the beef (whole) into a zip-lock bag. Combine all the marinade ingredients and pour into the bag. Seal the bag then agitate coat all the meat. Refrigerate for at least 4 hours, 24 hours is best.

Step 2

Drain the beans, and retain 1 cup of the liquid (if you need to top up the liquid with water, that’s OK).In a dry frying pan, toast the avocado leaves and arból chillies for a minute to release the aroma.Tip the beans, avocado leaves, arból and cooking liquid into a blender and blend to a smooth paste.Heat a large pan with the oil over a moderate heat and gently fry the onion and cilantro stems for 1-2 minutes until soft. Add the bean paste and the salt and stir well. Cook over a medium/low heat for 20-30 minutes, stirring regularly to avoid sticking. The beans should be thick! Check for seasoning and then leave to cool.

Step 3

Preheat oven to 350ºF/180ºCPlace 2 tortillas on a baking sheet (without overlapping). Bake in oven for 10-15 minutes until crisp. Repeat with the remaining tortillas and then leave to cool. You can do this in advance and leave, covered in a cool place - they'll stay crisp.

Step 4

Using a BBQ grill or a hot griddle pan, cook the steak for 2 minutes each side (or more depending how thick your steaks are). Cook until you have some good char on the outside.Let the steak rest for 1-2 minutes, then thinly slice.

Step 5

Using a spoon or spatula, smooth over a few spoonfuls of refried beans onto each tortilla. Scatter over some lettuce, cabbage and radish and then a few slices of steak. Finish with some Oaxacan cheese.When serving, offer a wedge of lime to squeeze over and if you're feeling generous, a little Mexican sour cream!