Preheat your oven to 375°F.
Season the chicken breast with garlic powder, salt, and pepper, then grill or sear it on a stovetop until just cooked through. Let it rest and then dice into bite-sized pieces.
Cook the whole wheat macaroni according to package directions until al dente, drain, and set aside.
Toss the broccoli with a pinch of salt, pepper, and a drizzle of oil if desired, and roast in the oven for about 12-15 minutes until tender and slightly charred.
In a small saucepan over medium heat, combine the nonfat milk and low-fat cream cheese. Stir continuously until the cream cheese melts into a smooth creamy sauce. Adjust seasoning with salt and pepper.
In a large bowl, mix together the cooked macaroni, diced chicken, roasted broccoli, and the creamy sauce. Ensure everything is evenly coated.
Transfer the mixture to a baking dish and warm in the oven for an additional 8-10 minutes to meld the flavors.
Serve hot and enjoy your high-protein, creamy macaroni bake.