Boil the pasta: Bring a large pot of salted water to a rolling boil.
Cook pasta until just al dente. Reserve 1 cup pasta water, then drain.
Blend the protein base: In a blender, combine cottage cheese, Greek yogurt, chicken broth, and half of the Parmesan. Blend until completely smooth and creamy.
Sauté the garlic: In a large skillet over medium heat, melt the butter.
Add minced garlic and cook 30–60 seconds until fragrant. Don’t brown it.
Make the sauce: Pour the blended mixture into the skillet. Stir gently over medium-low heat for 2–3 minutes until warmed and slightly thickened.
Avoid boiling.
Season and finish: Stir in remaining Parmesan, lemon juice, salt, and pepper. Adjust thickness with a splash of reserved pasta water if needed. The sauce should coat a spoon.
Add chicken and pasta: Fold in shredded rotisserie chicken and the drained pasta.
Toss until everything is coated and heated through. If using spinach or peas, add now and cook 1–2 minutes until wilted or warmed.
Taste and adjust: Add more salt, pepper, or lemon to balance. If you want extra richness, finish with a teaspoon of butter or a drizzle of olive oil.
Serve: Plate immediately.
Garnish with chopped parsley, extra Parmesan, and red pepper flakes if you like a little heat.