Pre-cook the noodles: Boil in salted water until just shy of al dente. Drain and set aside. You want them slightly firm so they don’t go mushy in the air fryer.

Prep the broccoli: If using fresh, blanch in the pasta water for 2 minutes, then drain. If using frozen, thaw and pat dry. Dry broccoli means less watery sauce.

Sauté aromatics: In a skillet over medium heat, add butter or oil. Cook onion until translucent, 3–4 minutes. Add garlic and cook 30 seconds until fragrant.

Make the sauce: Sprinkle flour over the onions and stir for 1 minute. Whisk in chicken broth slowly until smooth. Add milk, Dijon, Italian seasoning, salt, and pepper. Simmer 2–3 minutes until lightly thickened.

Add the cheese: Off the heat, stir in 1 cup shredded cheddar (or Gruyère) until melted and silky. Taste and adjust seasoning. A pinch of red pepper flakes perks it up.

Combine: In a large bowl, toss noodles, chicken, broccoli, and the cheese sauce until evenly coated.

Prepare the topping: Mix remaining 1/2 cup cheddar with Parmesan and breadcrumbs. Add a drizzle of olive oil or a quick spritz of cooking spray to help with browning.

Assemble: Lightly grease an air fryer-safe baking dish that fits your basket. Spread the mixture in an even layer. Sprinkle the breadcrumb-cheese topping over the surface.

Air fry: Preheat air fryer to 350°F (175°C) for 3 minutes if your model recommends it. Cook for 10–14 minutes, or until the top is golden and the edges are bubbly. If your air fryer runs hot, start checking at 8 minutes.

Rest and serve: Let the bake sit for 5 minutes to set up. Garnish with chopped parsley or chives if you have them.