3-6 eggs -  I use 3
1 can Eagle brand sweetened condensed milk - you can use the low fat, but never the non-fat
16 oz. whipping cream - use the ultra pasteurized
3 TBSP chocolate syrup
2 tsp. vanilla - the good stuff - not vanilla extract
 
Put the above ingredients in a blender and blend until smooth
Add 12 oz. Irish whiskey (again, use the good stuff)
Pour into a glass container and cover - store in the refrigerator
 
I think it takes a couple of days to get the good flavor, but if you aren't patient, drink now.
 
Cheers!