Place all the ingredients in a bowl and mix well.
Preheat oven to 425°F.
Cut the top quarter inch off each head of garlic.
Each individual clove should be visible and exposed.
Place the heads of garlic on tin foil and drizzle with oil.
Wrap up the garlic and place in oven for 30 minutes, until fragrant, soft, and golden.
Once the garlic has cooled, squeeze individual cloves out of the skin, into a medium bowl.
Combine mayonnaise, lemon, salt and pepper and parsley in the bowl with roasted garlic.
Stir until smooth and creamy. Reserve.