Heat the stock to @ 200 degrees, reserve.
Puree the spinach and reserve.
In a large heavy pot, combine the pancetta, nutmeg, garlic, thyme, shallots, ¾ of the butter and oil over low heat until the shallots are cooked through. Add the rice, stirring well to coat the rice with the oil, for 2 minutes.
When the rice becomes vaguely translucent add a few ladles of the stock to cover the rice barely, stir over the heat and keep adding stock as need to cover rice with a veil of liquid.
Keep cooking until rice is creamy, grains are distinct and separate and just al dente.
Stir in spinach and crème fraiche.
Cook for a few minutes more.
Add the rest of the butter and ½ the cheese, stirring gently.
Let sit for 60 seconds and serve passing the rest of the cheese.