Cook fettuccine according to package directions.
Meanwhile, over medium heat melt the butter in a small saucepan.
Add garlic and green onion, cook until onion and garlic are lightly cooked, about 2 to 3 minutes.
Add the flour and salt, stir to blend.
Lightly brown the flour, add chicken broth, half-and-half, parsley and creme fraiche.
Stir in Emeril's Essense and crab, stir to blend.
Turn heat down to low and simmer, stirring frequently until crab is thoroughly warmed and sauce thickened.
Serve sauce over cooked fetuccine and grate Parmesan Reggiano cheese over all.
Serve immediately.
