Heat ½ tbs of oil in a large non-stick frying pan over a medium heat.
Add the onion and sauté for 2 minutes.
Add the mushrooms and cook for 4 - 5 minutes or until tender. Set aside
Combine the flour, cumin seeds and seasoning together in a bowl and toss the beef strips through the flour to coat each side.
Heat ½ tbs oil in a non-stick pan and cook half the beef over a high heat until browned. Remove the browned meat and repeat the process with the remaining oil and beef.
Return the mushroom mixture and beef to the frying pan and add the stock and lemon juice.
Bring to the boil. Reduce the heat to simmer for about 10 minutes or until the sauce has thickened slightly. Remove from the heat.
While the beef is cooking, stir fry the cauliflower rice in a wok for 3 - 4 minutes until heated through.
Stir in the Greek yoghurt through the beef and serve over the cauliflower rice.