OK, here's the recipe:

POTATO AND CHEDDAR SOUP
Serves 6-8

3 lbs. white potatoes, peeled and sliced
1 lb sour cream
3 Tablespoons butter or olive oil
2 Tablespoons flour
1 lb.mushrooms (whole if small, otherwise halve or quarter)
3 cloves garlic, well chopped
1/2 -1 teaspoon ground black pepper
2-3 sprigs of fresh rosemary

Place the potatoes and garlic in a 6 quart pot. Cover with lightly salted water and boil until tender. Drain, saving the liquid. Add the sourcream and mash and stir until the potatoes are somewhere between chunky and smooth. Add some of the retained liquid to form a thick soup. Chop up the rosemary leaves and add with the ground pepper.

In another pan, make a roux with the butter and flour. When the roux is brown, add the mushrooms and stir until well coated. Then dump them in with the potatoes. Add salt to taste. Simmer for 15 - 20 minutes.

To serve, place about 1/2 cup of grated cheddar cheese in a bowl and ladle the soup on top. Allow your guests to stir according to their whim.