Boil the Pasta: Bring a large pot of salted water to a rolling boil. Add Barilla penne pasta and cook for about 8–10 minutes until al dente. Reserve 1 cup of pasta water before draining.

Prepare the Salmon: Pat salmon filets dry, season with salt and black pepper. Cut into bite-sized chunks.

Sauté the Salmon: Heat 2 tablespoons of olive oil in a skillet over medium-high. Cook salmon chunks for 3–4 minutes per side until golden. Remove from skillet.

Cook the Aromatics: In the same skillet, add finely diced onions and sauté for 2–3 minutes. Add butter, garlic, and parsley; cook for another minute.

Create the Sauce: Add salmon back to the skillet, sprinkle red pepper flakes. Gradually stir in lukewarm milk and simmer until thickened. Mix in reserved pasta water and parmesan.

Combine Pasta and Sauce: Add cooked penne to the sauce, folding gently to coat. Adjust thickness with reserved pasta water if needed.

Finish and Serve: Garnish with lemon zest, extra parmesan, and red pepper flakes. Serve immediately.