Preheat the oven to 375°F (190°C).
Heat the olive oil in a large skillet over medium-high heat.
Add the chicken pieces to the skillet and cook for 5-7 minutes until lightly browned and cooked through. Remove chicken from skillet and set aside.
In the same skillet, add the diced onion and minced garlic. Sauté for 2-3 minutes until the onion is translucent.
Add the red bell pepper, broccoli florets, and sliced mushrooms to the skillet. Cook for 5 minutes, stirring occasionally, until the vegetables are tender.
In a large mixing bowl, combine the cooked chicken, sautéed vegetables, low-fat cottage cheese, Greek yogurt, chicken broth, dried oregano, dried thyme, paprika, salt, and black pepper. Mix well.
Transfer the mixture into a greased 9×13 inch casserole dish and spread evenly.
Sprinkle the shredded cheddar cheese and grated Parmesan cheese evenly over the top.
Bake uncovered in the preheated oven for 25 minutes, or until the casserole is bubbly and the cheese is melted and golden.
Remove from the oven and let it rest for 5 minutes.
Garnish with chopped fresh parsley before serving.