In a small saucepan place the
Chablis, white wine vinegar, garlic, shallots, and anchovies.
Heat the ingredients on medium
low and simmer them for 8 to 10 minutes, or until the liquid is
reduced to 1/4 cup.
Strain the liquid. In a blender
place the basil and the strained, reduced liquid.
Puree the ingredients until they
are smooth. Add the egg yolks and the lemon juice, and puree
them. While the blender is running, slowly add the olive oil.
Season the sauce with the salt