Place all the spices into a small bowl (paprika, pepper, oregano, spearmint, cumin powder, curry powder) and mix well.

Place the tomato sauce, the mustard, the garlic (finely chopped) and the vinegar into another bowl. Mix well.

Wash the steaks well and place them in a large bowl.

Sprinkle the 2 steaks with half of the spice mixture.

Using a spoon, coat them all over with half the dressing mixture.

Pour oil over them.

Turn the steaks upside down and add the rest of the ingredients in the same way.

Cut the onion into round slices and place them on top of the steaks (place some onion under them as well).

Cover the bowl with aluminum foil and set it aside at room temperature for 3 hours.

Season with salt after the 2 1/2 hours have past (on both sides of the steaks).

Barbecue or grill them for 40-45'.

Place them in a large pyrex tray and pour the juice of one lemon over them. Mix well.