Melt the butter in sauce pan.
Add the onion and cook until golden.
Add the crabmeat and parsley and cook over low heat stirring constantly for approximately 5 minutes.
Add the flour, stir to blend and cook for 3 minutes more
Stir in the chicken broth and simmer for 20 minutes.
Add the cream and cayenne pepper
Simmer for 5 more minutes.
Server warm.