Prep the noodles: Break the lasagna noodles into roughly 2-inch pieces. Set aside.
Have all other ingredients measured and ready—this keeps the process smooth.
Sear the chicken: Heat 1 tablespoon olive oil in a large, deep skillet over medium-high. Season the diced chicken with salt and pepper, then cook in a single layer until lightly browned and just cooked through, about 5–6 minutes. Transfer to a plate; keep any juices in the pan.
Sauté aromatics: Reduce heat to medium.
Add another teaspoon of olive oil if the pan is dry. Add the chopped onion and a pinch of salt, cooking 3–4 minutes until translucent. Stir in minced garlic, Italian seasoning, and a small pinch of crushed red pepper; cook 30 seconds until fragrant.
Build the cooking liquid: Pour in 3 cups low-sodium chicken broth and 1 cup milk.
Bring to a gentle simmer, scraping up any browned bits for flavor.
Add noodles: Stir in the broken lasagna noodles, making sure they’re mostly submerged. Adjust heat to maintain a lively simmer, not a boil. Cook uncovered, stirring every 2–3 minutes to prevent sticking, until noodles are al dente, about 10–12 minutes.
Add a splash of broth or water if the pan looks dry.
Make it creamy: Reduce heat to low. Whisk the Greek yogurt (1/2 cup) and softened Neufchâtel or light cream cheese (2 ounces) together in a small bowl until smooth. Temper by stirring in a few spoonfuls of the hot cooking liquid.
Then fold this mixture into the skillet along with 1/3 cup grated Parmesan. Stir gently until the sauce is creamy and slightly thickened.
Add chicken and greens: Return the cooked chicken and any juices to the skillet. Stir in 3–4 cups baby spinach until just wilted, 1–2 minutes.
Finish with brightness: Add the zest of 1/2 lemon and 1–2 teaspoons lemon juice.
Taste and adjust salt and pepper. If you want extra richness, sprinkle 1/2 cup part-skim mozzarella over the top, cover for 1–2 minutes, and let it melt.
Rest and serve: Let the skillet sit off heat for 3–5 minutes to thicken slightly. Garnish with chopped parsley or basil.
Serve warm with a side salad if you like.