Clean, wash and thinly slice the zucchini. Dice the gherkins. Clean, wash and finely dice carrots. Wash, peel and finely dice potatoes. Heat olive oil in a frying pan, add potatoes and fry for 5 minutes over medium heat while turning.
Add carrots and zucchini and steam for another 5 minutes. Deglaze with vinegar and season with salt, pepper and sugar. Add gherkins and herbs. In the meantime heat oil in a pan and fry fish fillets in it at medium heat while turning for 8-10 minutes.
Arrange salad and fillets (drizzle remaining salad vinaigrette over the fish) on two plates and serve garnished as desired with lemon and parsley.