Preheat oven to 375*F.
Drain artichokes, reserve.
Drizzle peeled garlic with olive oil, wrap in foil and place in oven. After 30 minutes, check doneness by inserting a knife tip into a clove. Once completely roasted, remove garlic and allow to cool.
Puree the cream cheese, milk, garlic, cayenne, salt, pepper and lemon juice in a food processor until smooth, about 1-2 minutes, scraping down side once during the mixing.
Add the mayonnaise, artichokes, green onions and parmesan.
Pulse mixture until fully incorporated, about 10 pulses, scraping down the side once during mixing.
Transfer to a container and chill in the refrigerator until service.