Steam whatever veg is around - I used tender stem brocolli and green beans. Fried a finely sliced onion in a dribble of olive oil, added steak and browned, added mushrooms. Stir for a couple of minutes and chopped mushrooms. Stir again for a couple of minutes, tip in veg and sauce (spoonful of tomato puree, splodge of american mustard, Lea and Perrins, black pepper - let down with the same volume of water, stir until smooth). Bubble mixture for a couple of minutes to ensure that the tomato paste is fully heated through, then chuck in big handful of spinach. Served on a few raw spinach leaves. Kind of an English stir fry.