Peel or clean and wash the vegetables. Cut carrots into large pieces, kohlrabi into slices. Cut cauliflower and broccoli into florets. Wash herbs, chop finely. Roast almonds until golden brown. For the sauce put milk and cream in a pot.
Stir in the sauce powder. Bring to the boil briefly while stirring. Set aside.
Cook the vegetables one after the other in boiling salted water for about 10 minutes (broccoli only 5 minutes). Lift them out, season with pepper if necessary and keep warm. Heat the sauce again and only add 250 g butter in pieces.
Stir in lemon peel and lemon juice. Heat 75 g butter. Arrange vegetables. Sprinkle with butter and partly cover with hollandaise sauce. Sprinkle cauliflower with herbs, broccoli with almonds. Garnish with lemon and chervil.
Serve the rest with hollandaise.