Wash the flowerets of cauliflower and let them stand in salted cold water for 1 hour. Rinse.
Cook flowerets in 2quarts of water with 1tablespoon salt until cooked but still firm.
Meantime make the sauce: mix beaten egg yolks, sour cream, heavy cream, lemon juice, pinch of salt and pinch of sugar; cook in the top part of a double boiler for 5 minutes, whipping constantly. Set sauce aside, but try to keep it warm.
Mix together bread crumbs, ½teaspoon salt and the white pepper.
In a separate bowl mix together the whole eggs and the milk.
Dip the drained and dried cauliflower first into egg and milk mixture, then into the bread-crumb mixture.
Heat the vegetable oil to 365°F., then turn heat to low. Carefully put the breaded cauliflower pieces into the oil and fry slowly until golden brown. Drain on absorbent paper.
Put the sauce on the bottom of a serving dish and place cauliflower on top of the sauce.