Bring a large pot of salted water to a rolling boil. Cook linguine until al dente according to package directions (about 9 to 10 minutes). Reserve 1/2 cup starchy pasta water, then drain pasta.

Pat shrimp completely dry with paper towels. Season both sides with garlic powder, smoked paprika, kosher salt, and black pepper.

Heat olive oil and 1 tablespoon butter in a large skillet over medium-high heat until shimmering. Add shrimp in a single layer and sear for 1 1/2 to 2 minutes per side until pink, opaque, and lightly caramelized. Transfer shrimp to a warm plate.

Melt remaining 2 tablespoons butter in the same skillet over medium heat. Add minced garlic and sliced sun-dried tomatoes. Sauté for 1 minute until wonderfully fragrant.

Pour in broth, scraping up all flavorful browned bits from the pan bottom. Simmer for 2 minutes to reduce slightly, then turn heat to low and whisk in heavy cream and red pepper flakes. Gently simmer for 3 minutes until sauce begins to thicken.

Stir in grated Parmesan until melted and glossy. Add baby spinach and stir for 1 minute until wilted into the cream sauce.

Toss cooked linguine and seared shrimp into the bubbling sauce, adding a splash of reserved pasta water if needed to coat the pasta ribbons. Garnish with chopped parsley and serve immediately!