For the risotto a la milanese, melt 4 tsp butter over moderate heat. Saute the onions in the butter for 7-8 minutes, stirring frequently. Do not let them brown, add the risotto rice and cook slowly, stirring, until the grains are shiny and a tiny bit translucent.
Pour in the wine and continue cooking until it is absorbed. Add 2 more cups of soup and continue to cook, stirring occasionally.
Now add the saffron. Continue to cook until the liquid is absorbed. Continue to add soup until rice is cooked but still a bit firm to the bite.
Stir in 4 tablespoons of butter and the grated cheese with a fork, being careful not to crush the rice. Season to taste with salt and pepper.
Serve the risotto a la milanese hot.