Peel, wash and slice the carrots. Peel, wash and halve the potatoes. Bring carrots and potatoes to the boil in 500 ml stock and simmer at medium heat for about 20 minutes.
Meanwhile melt fat in a pot, dust with flour, sweat, gradually add 250 ml broth and milk and bring to the boil while stirring. Stir in mustard. Season to taste with sugar, salt and pepper.
Keep warm. Wash the rocket, shake dry and, except for a few leaves for garnishing, finely chop the rocket. Cook the eggs in boiling water for about 8 minutes, drain, quench and remove the shell. Drain potatoes and carrots, collect the stock and measure 200 ml.
Coarsely mash the potato and carrot mixture with a potato masher and pour on the measured stock. Season to taste with salt and nutmeg. Add finely chopped rocket to the sauce. Sprinkle pepper over carrot-potato puree, sauce and one halved egg each and arrange rocket on plates.