Saute onions and mushrooms in olive oil until browned and all pan juices have evaporated, then add pourgouri and brown, stirring.
When wheat is golden and nutty reduce heat and add water, stock, cube and butter.
Close the pot with a lid and allow to cook for 15-20 minutes ( do not stir as this makes wheat mushy and we want a loose and flanky result ).
When pourgouri is cooked gently stir in the grated tomato, taste for salt and pepper and remove from heat.
Allow to stand for 20 minutes and serve.
Serve with yogurt.
Cracked pistaccio nuts can be sprinkled as a garnish.
This dish can be also served cold as a salad.