1) Cook the spinach in boiling water unti it turns soft. Drain and squeeze out all extra water. Chop the spinach finely and keep aside.
2) In a saucepan, melt butter and oil and saute onions until they become soft. Add the rice and cook for 2 minutes.
3) Add in 1/2 cup of stock and adjust the heat so that the rice continues cooking in the stock. When the liquid is absorbed, add in another 1/2 cup of stock. Continue adding more stock until rice is thoroughly cooked in about 20 to 25 minutes.
4) Add in chopped spinach and pine nuts and remove the rice from the flame.
5) Add in the cheese and stir well.