Season both sides of each salmon fillet evenly with 0.5 teaspoon of kosher salt and 0.3 teaspoon of black pepper.

Heat the olive oil and 15 ml of butter in a large heavy skillet over medium-high heat until hot and shimmering. Add the salmon fillets flesh-side down and sear undisturbed for 4 to 5 minutes until crisp and golden brown. Flip carefully and cook the reverse side for another 3 to 4 minutes until almost cooked through. Transfer fillets to a warm plate and set aside.

Reduce skillet heat to medium. Melt the remaining 15 ml of butter in the skillet, then add the minced garlic and sliced sun-dried tomatoes. Saute for approximately 1 minute until fragrant, stirring continuously to prevent the garlic from browning.

Pour in the chicken broth to deglaze the skillet, bringing it to a simmer for 1 to 2 minutes until reduced by half. Stir in the heavy cream and bring the liquid to a gentle bubble, then fold in the grated Parmesan cheese and remaining 0.3 teaspoon salt until melted and smoothly incorporated.

Add the baby spinach leaves to the skillet and gently fold them into the sauce until wilted, about 1 to 2 minutes. Stir in the fresh lemon juice, then nestle the seared salmon fillets back into the simmering sauce. Spoon the warm cream sauce over the fillets and heat through for 1 to 2 minutes before removing from heat.