This has always been a hit with my guests and is one of my favourite pasta dishes. Although its advisable to make the chicken sauce at the last minute, you can make the tomato sauce in advance, refrigerate & reheat. The chicken sauce tastes as good made with half & half but it takes longer to thicken. The dish can be made with any pasta - it doesn't have to be green - only if you want the tri-colour (neapolitan) presentation.