Bring a large pot of water to a boil. Add 1-1½ tablespoons of salt to the water and cook the pasta according to the package. Reserve ½ cup of pasta water for the sauce before draining.
Season the salmon with 1 teaspoon salt and pepper.
Heat 1 tablespoon of olive oil in a large skillet over medium heat. Add the salmon and cook for 4 minutes on one side, flip, and cook for an additional 4 minutes. Remove the salmon from the pan to a cutting board or plate.
Add the remaining olive oil, garlic, and onion to the pan. Saute for 3 minutes, until the onion starts to become translucent and the garlic becomes fragrant. Season with the remaining teaspoon of salt.
Add the cherry tomatoes and saute for 2 minutes.
Pour in the pesto, reserved pasta water, and red pepper flakes and stir to combine. Bring the sauce to a simmer.
Toss the pasta in the pesto sauce. Use a fork to flake the salmon.
Spoon the pasta into individual bowls, top with salmon, serve and enjoy!
