Creamy Tuscan Salmon

Name: Creamy Tuscan Salmon
Ingredients: 1/4 cup loosely packed fresh parsley leaves; 3 cloves garlic; 1 (7- to 8-ounce) jar sun-dried tomatoes packed in oil; 1 ounce Parmesan cheese, finely grated (about 1/2 firmly packed cup grated on a Microplane or 1/3 cup store-bought); 4 (6-ounce) skin-on salmon fillets; 1 1/2 teaspoons kosher salt, divided; 1/2 teaspoon freshly ground black pepper, divided; 3 tablespoons olive oil, divided; 1/4 teaspoon red pepper flakes (optional); 5 ounces baby spinach (about 5 packed cups); 1 cup half-and-half