Season 4 salmon fillets with salt and pepper to taste on both sides. In a large skillet over medium heat, melt 1 tbsp butter. Once melted, drizzle 1 tbsp olive oil into the pan and give it a good stir. Add salmon to the pan in a single layer. Sear, undisturbed, for 4-5 minutes until browned, carefully flip and cook another 5-7 minutes (depending on the thickness of your salmon pieces) until cooked through. Transfer salmon to a plate and cover tightly with foil to keep warm and moist. For the Sauce: Add 1 tbsp butter and 3 tsp minced garlic to the pan and stir over medium heat for about 2 minutes until butter is melted and garlic is fragrant. Stir in 1 c chicken broth and simmer about 5 minutes until reduced by half. Stir in 1 c baby spinach for about 1 minute until wilted. Stir in 3/4 c. heavy cream, and 4 ounces cream cheese, at room temperature or softened in the microwave. Continue to gently stir until cream cheese is completely incorporated and sauce is creamy and smooth. Season with salt and pepper. Taste, add more salt and pepper if needed. Return salmon to the pan, spoon the creamy spinach sauce over the salmon, and serve.