You proceed as for any risotto, beginning with a soffritto of chopped onion or, better yet, shallot sweated in butter (or butter and oil). Then add finely chopped radicchio and allow it to wilt and absorb the flavor of the onion and butter.
Raise the heat, add your rice and allow it to lightly 'toast' until it becomes opaque (remember, the rice should not actually brown at all) then add a splash of dry white wine.
When the wine has evaporated, proceed as usual, adding a ladleful of vegetarian broth at a time, until rice is almost cooked al dente.
Just before the rice is done, add a good chunk of Saint-André cheese, together with a handful of grated parmesan cheese and, if you like, just a spoonful or so of cream. Mix vigorously until the cheese has entirely melted and amalgamated with the rice.
Serve immediately.