Tortellini with Creamy Mushroom Sauce

2 - 9oz packages fresh cheese tortellini
1/4 C butter
3/4 lb shiitake mushrooms
2 shallots, chopped
1 1/4 C white wine
1/2 C whipping cream
6 fresh sage leaves, chopped
coarse salt and freshly grounded pepper, to taste

1) In a large pot of salted water, cook the pasta according to package directions. Drain
2) Melt butter in a heavy skillet over medium heat. Add the shallots and saute for 1 minute. Add the mushrooms, saute until brown about 7 minutes. Add the wine and cream and boil until the sauce thickens and coats a spoon, about 5 minutes. Stir in the sage and season with salt and pepper.