Cook the pasta in a large pot of well-salted boiling water according to the package directions for al dente. Reserve about ½ cup of the pasta cooking water; drain off the rest.
While the pasta cooks, heat the olive oil in a large skillet or Dutch oven over medium-high heat. Add the shrimp; sprinkle with the all-purpose seasoning blend and ground black pepper to taste. Cook, stirring frequently, until the shrimp turn pink and opaque, about 3 minutes for jumbo shrimp or less if the shrimp are smaller. Remove from the heat.
Add the drained pasta, pesto, butter, and ¼ cup of the reserved pasta cooking water to the pan with the shrimp. Cook over low heat, tossing gently, just until the butter melts and the ingredients come together, about 1-2 minutes. Add more pasta water, as needed, to thin the sauce.
Garnish with grated Parmesan, chopped fresh herbs, and a squeeze of fresh lemon juice, if desired.