Bring a large pot of salted water to a boil and cook pasta. Drain.
Meanwhile, melt butter in a medium saucepan over medium heat. Add garlic and sauté for one minute, do not brown the garlic.
Stir in cream and pepper. Cook for 6 to 8 minutes, stirring frequently.
Add Parmesan cheese and gently stir until smooth. Mix in pesto and cook for 3 to 5 minutes until thickened.
Taste sauce and add salt as necessary. You want your sauce to taste just a bit more salty than what you want the final flavor on the pasta to be. Keep warm, but do not boil.
In a large sauté pan, heat olive oil until shimmering over medium heat. Add shrimp (or seafood mixture) and sauté until the shrimp is fully pink and other seafood is just cooked through. Do not over cook!
Toss cooked pasta with sauce and seafood. Garnish with a little chopped fresh parsley, if desired.
Toss together only as much pasta as you will eat immediately. If you plan on having leftovers, keep leftover pasta, sauce and seafood separate for reheating.