Preheat the oven to 375°F (190°C). Grease a medium baking dish with a little olive oil.
In a skillet, heat olive oil and sauté the onion and garlic until soft and fragrant.
Add the zucchini slices and cook for 3 to 4 minutes until slightly tender but not mushy.
Layer half of the zucchini in the baking dish, followed by half of the shredded chicken and cherry tomatoes.
Sprinkle with oregano, basil, salt, and pepper. Top with half of the mozzarella and parmesan.
Repeat the layers with the remaining zucchini, chicken, and cheese.
Bake for 25 to 30 minutes, until the top is golden and bubbly.
Remove from the oven, let cool slightly, and garnish with fresh parsley before serving.