Peel and wash the potatoes and cook them in boiling salted water for about 20 minutes. Clean, wash and roughly chop the rocket. Roast the pine nuts in a pan without fat until golden brown, take them out.
Peel the garlic. Put rocket, pine nuts, parmesan and garlic in a blender. Fill up with olive oil and puree. Season with salt and pepper. Wash, clean and slice the tomatoes.
Wash and clean the cucumber and cut or slice it thinly. Mix vinegar, salt, pepper and sugar. Fold in 2 tablespoons of olive oil. Place the cucumber and tomatoes in a bowl and mix with the vinaigrette.
Drain the potatoes, let them evaporate and press them through a potato press while still hot. Wash and grate the zucchini. Squeeze out excess liquid. Stir the grated zucchini, egg yolks and starch thoroughly into the potato mixture.
Season with salt and pepper. Form a roll (5-6 cm Ø) from the mixture and cut into 20 thalers. Heat the oil in portions in a frying pan and fry the thalers in portions until golden brown, turning them over.
Arrange the potato cookies together with the tomato-cucumber salad and drizzle with the pesto.