Cook the pasta according to package directions. Drain, reserving about 1/2 cup cooking liquid, if desired, and set aside.

In a large skillet, heat the olive oil over medium heat. Add the sun-dried tomatoes, garlic and onion and sauté, stirring often, until the onion is translucent, about 5 minutes. Slowly add the flour, while stirring. Let cook for 1 minute. Slowly whisk in the milk, ensuring there are no clumps. Add the milk, while whisking, and let simmer for 5 minutes, until thick and creamy. At this point, you may want to add more milk or the pasta cooking liquid, to achieve the desired consistency. Add sea salt and pepper, to taste. Combine the pasta with the sauce and serve, garnished with fresh basil. Bon appétit!