Cook pasta according to package directions. Drain, rinse and set aside.

Meanwhile, melt the butter with the garlic oil in a large skillet over medium-low heat. Add the gluten-free flour and stir until smooth. Slowly pour in the milk, while constantly whisking. Keep whisking until the mixture thickens and comes to a simmer (it's important to keep stirring so the sauce thickens evenly).

Stir in the flaked salmon, scallions, capers, lemon juice and cooked penne pasta. Cook until heated through and season with salt and pepper.

Serve sprinkled with parsley and Parmesan cheese.