Preheat the oven to 375°F (190°C) and lightly grease a baking dish.
Place sliced zucchini in a colander, sprinkle lightly with salt, and let sit for 10–15 minutes, then pat dry thoroughly.
Heat olive oil in a skillet over medium heat and lightly sauté the zucchini for 3–4 minutes to remove excess moisture.
In a large bowl, mix cooked chicken, Greek yogurt, eggs, garlic, salt, pepper, and smoked paprika until well combined.
Gently fold the cooked zucchini into the protein mixture.
Transfer the mixture to the prepared baking dish and spread evenly.
Sprinkle mozzarella and cheddar evenly over the top.
Bake uncovered for 30–35 minutes until bubbly, lightly golden, and set in the center.
Remove from oven and rest for 10 minutes before slicing and serving.