Good question! I have been to dinner parties before where the guests have had to wait for over 2 1/2 hours to eat. You don't want to keep your guests waiting too long so make sure your food is ready or almost ready by the time guests arrive.
You can serve drinks and snacks and then serve the meal after about 45 minutes to an hour. If guests are socializing well and there are plently of snacks you may want to wait a little longer.
However you don't want to keep your guests waiting too long and if your dish is taking much longer than you expected, make sure that you have plenty of snacks on hand to avoid unnecessary hunger pangs!
