Peel, wash and cut the potatoes into pieces. Cover and cook in boiling salted water for about 20 minutes.
Cleaning and washing the zucchini. Cut off a thick slice lengthwise and put it aside as a lid. Hollow out the zucchini and season with salt and pepper. Coarsely chop the hollowed out zucchini flesh.
For the sauce, peel and finely dice the onion. Wash the thyme, shake dry and remove the leaves. Heat the oil in a pan. Sauté the onion in it. Fry the chopped zucchini and thyme.
Season with salt and pepper. Pour 400 ml of water and bring to the boil. Remove from the heat, let it cool down a little and puree it finely with a hand blender.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Sort the rocket, wash, drain well and cut into strips. Peel garlic and chop finely. Drain potatoes.
Mash the potatoes, garlic and milk into a puree. Stir in butter. Season with salt and pepper. Fold in rocket.
Fill the zucchini with puree and place them in a large ovenproof dish or on the fat pan (deep baking tray). Pour on the sauce. Bake in a hot oven for 40-45 minutes. After about 20 minutes sprinkle almonds over the zucchini.
Slide the zucchini lid over the zucchini on a rack and bake with them. Arrange everything.