Cook pasta in a large pot of boiling water until done. Drain.
Meanwhile, melt butter in a small saucepan over very low heat. Add Worcestershire sauce and Tabasco to taste; mix well. Stir in lemon juice, mixed herbs, bay leaf and thyme. Keep warm, but do not simmer.
Heat oil in large frypan. Saute prawns in oil for 3 to 4 minutes or just until prawns turn pink. Pour off all but 1 tablespoon liquid from frypan. Remove and discard bay leaf. Add butter sauce and stir well. Stir in parsley. Serve over angel hair pasta.