Finely dice the onion and sauté in hot oil until translucent.
Halve the zucchini lengthways, hollow out the pulp and finely chop. Also add to the pan and sweat while stirring until the liquid has evaporated. Salt and pepper.
Dice peeled potatoes and add to the pan with the broth with the zucchini meat, cook until al dente. Simmer uncovered until the liquid has almost evaporated.
Preheat the oven to 160 ° C
Add cream cheese and shrimp or boiled ham (as desired) - or, if you have a vegetarian option, just add cream cheese. Spread the hollowed out zucchini halves in a baking dish or baking tray and fill with the potato mixture. Spread the parmesan on top. Put in the oven and bake for 10 minutes, then turn on the grill for another 10 minutes.