First, marinate the beef for at least 1 hour.
After, add in oil to a saucepan and sear the beef on both sides until rare or medium rare.
Take it out and cut into bit size pieces.
In the same pot (don't rinse it) add in the onions and garlic and saute until fragrant, add in the remaining marinade, tomato puree, water or stock, lemon juice and season and cook until slightly thick and bubbly.
Then, add in the beef and cook stirring frequently until the beef is cooked to your taste.
For the yoghurt sauce, combine all the ingredients in a small bowl and leave for about 5 minutes to absorb more of the garlic flavour.
Char the tortilla in a pan and wrap around a rolling pin for about 30 seconds to hold it's shape.
Finally, assemble the taco in whatever order you prefer. Enjoy!
