Prepare the Napolitan Sauce:
Heat the olive oil in a large skillet over medium heat. Add the chopped onion and diced red bell pepper. Cook until softened, about 5 minutes.
Add the ground pork to the skillet. Cook, breaking up the meat with a wooden spoon, until browned and cooked through, about 8-10 minutes. Season the pork mixture with salt, pepper, and dried oregano. Pour in the diced tomatoes with their juices an the basil leaves chopped. Stir well to combine. Reduce the heat to low and let the sauce simmer for 15-20 minutes, stirring occasionally, until thickened. Remove from heat and set aside.
Prepare the Zucchini:
Preheat the oven to 375°F (190°C). Cut off the ends of each zucchini and slice them lengthwise into thin strips using a vegetable peeler or mandoline slicer. Aim for about 12 slices per zucchini.
Assemble the Cannelloni:
Lay out two zucchini slices and place a spoonful of the Napolitan sauce along one edge.
Roll up the zucchini slice tightly, enclosing the filling, and place it seam-side down in a baking dish. Repeat with the remaining zucchini slices and Napolitan sauce until all the zucchini slices are used up.
Bake the Cannelloni:
Once all the zucchini cannelloni are assembled in the baking dish, cover them with the low-fat mozzarella cheese slices.
Bake in the preheated oven for 20-25 minutes, or until the cheese is melted and bubbly and the zucchini is tender.
Serve:
Remove the zucchini cannelloni from the oven. Top generously with mozzarella cheese slices. Let them cool for a few minutes before serving. Garnish with fresh herbs if desired.
Enjoy this delicious and healthy twist on classic cannelloni!