Preheat your oven to 190°C (375°F). Use a sharp spoon to carefully cut each zucchini in half lengthwise, then scoop out the centers, leaving about 1/4 inch of flesh around the edges. Set aside the scooped-out flesh for the filling.
Finely chop the zucchini flesh and place it in a mixing bowl. Add the shredded cheddar and mozzarella cheeses, chopped basil and parsley, lemon juice, a pinch of salt, and pepper. Mix everything together until well combined.
Stuff each zucchini half generously with the prepared filling, pressing down slightly to pack it in. Arrange the stuffed zucchinis in a baking dish, then drizzle the tops lightly with olive oil for a crispy finish.
Sprinkle the toasted panko breadcrumbs evenly over the stuffed zucchinis to add a crunchy topping. Place the dish in the preheated oven and bake for 25-30 minutes, until the zucchinis are tender and the cheese is bubbling and golden around the edges.
Remove the dish from the oven and allow the zucchinis to rest for about 5 minutes. This helps the filling set and makes serving easier. Garnish with extra herbs if desired, then serve warm with a side salad or crusty bread.
