From The Surreal Gourmet.

1 raw or coddled egg yolk
juice of half a lemon
1 tbsp Anchovy paste
2 tsp Dijon mustard
2 cloves crushed garlic (I use the kind that comes in a jar)
4 or 5 drops Worcestershire sauce
4 shakes Tabasco
1/3 cup olive oil
salt, pepper
freshly grated Parmesan cheese

Whisk together egg yolk, anchovy paste, mustard, garlic, Worcestershire Sauce, Tabasco, salt & pepper.
Add lemon juice and whisk some more.
Slowly trickle in olive oil while whisking.
Toss crisp Romain leaves with 2 tbsp of this dressing and add grated Parmesan. Yum Yum.