Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a large bowl, add ½ cup of the grated Parmesan cheese, breadcrumbs, olive oil, and garlic powder and dash of salt and pepper. Stir until well combined.
Add the chicken thighs to the bowl and toss until the chicken is evenly coated with the Parmesan mixture.
Transfer the coated chicken to the prepared baking sheet, spreading it out in a single layer. Bake for 30 minutes, or until the chicken is cooked through and lightly golden (chicken reaches minimum temperature of 165 °F (74 °C)).
While the chicken is baking, bring a large pot of salted water to a boil. Cook the pasta according to package directions, about 10 minutes, until tender, then drain and return pasta to the pot.
While the pasta cooks, finely dice the spinach and mushrooms. Heat a small amount of olive oil in a frying pan over medium heat. Add the mushrooms and cook for 3-4 minutes until softened, then add the spinach and cook just until wilted. Remove from heat.
Return the drained pasta to the pot. Add the sautéed spinach and mushrooms, remaining grated Parmesan cheese, milk, and olive oil. Stir gently to combine, adding a splash more milk if needed.
Once the chicken is done, remove it from the oven and let it cool slightly. Cut the chicken into bite-sized pieces and spoon over the pasta before serving.
This dish can be served family-style and deconstructed if that works better for your child. You can offer plain pasta, chicken pieces, and vegetables separately on the table and let everyone build their own plate. This keeps the meal low-pressure while still sharing the same foods as a family. Ensure there is at least one already accepted food being offered.