Preheat the oven to 400°F (200°C).
Bring a large pot of salted water to a boil. Cook the linguine according to package directions until al dente. Drain and set aside.
In a large Dutch oven or any oven-safe dish, add the salmon fillets, olive oil, Boursin cheese, spinach, cherry tomatoes, garlic, capers, Italian seasoning, salt, and pepper. Cover the dish with a lid or foil and bake for 20–30 minutes, or until the salmon flakes easily with a fork and the tomatoes have softened.
Remove the dish from the oven and gently flake the salmon into bite-sized pieces. Stir everything together until the cheese is melted and well combined into a creamy sauce.
Add the cooked linguine and toss until fully coated in the Boursin sauce. Serve hot with fresh herbs or a squeeze of lemon, if desired.
