Peel the garlic and press it through a garlic press. Halve the avocados and remove the flesh from the skin. Cut 1/4 of the flesh into small cubes. Finely puree the remaining ##avocado##, garlic and 2-3 tbsp. lemon juice.
Stir in butter##milk##, season with salt and pepper. ##Stir in crab and avocado cubes.