1. Preheat oven to 400º.
2. Wipe mushrooms clean and remove stems.  Set caps aside and finely chop stems.  Finely chop shallots.
3. Heat olive oil over low heat and add shallots.  Cook 1 minute, stirring constantly, and add chopped mushroom stems.  Cook 1 more minute.  Remove from heat and set aside to cool.
4. Mash and mince garlic cloves and combine with toasted pine nuts, nutmeg, Tabasco sauce, Worcestershire sauce and beaten egg.
5. Grate Havarti cheese and add to stuffing mixture.  Stir in cooled sautéed mushrooms and shallots, and blend well.
6. Rub mushroom caps inside and out with softened margarine or butter, and place in shallow baking dish.
7. Mound stuffing into each mushroom cap, and pack with fingers or the back of a spoon.
8. Bake uncovered in 400º oven 10 to 15 minutes, depending on size of mushroom caps.  Serve immediatly as hor d'oeuvres, first course or entrée.

Variation:  Three-fourths cup cooked ham, shrimp, crabmeat or lobster may be substituted for grated cheese.  A little lemon juice complements a seafood stuffing.