Season salmon fillets on both sides with salt and black pepper.
Heat olive oil in a large skillet over medium-high heat.
Place salmon fillets in the skillet skin-side up and sear for 4 to 5 minutes until golden brown.
Flip the fillets and cook for another 3 to 4 minutes or until the internal temperature reaches 145 degrees Fahrenheit. Remove salmon from the pan and set aside.
In the same skillet over medium heat, add minced garlic and sauté for 1 minute until fragrant.
Whisk in the harissa paste and heavy cream, bringing the mixture to a gentle simmer.
Add baby spinach and stir until the leaves have wilted into the sauce.
Stir in lemon juice, then return the salmon fillets to the skillet.
Spoon the creamy sauce over the salmon and garnish with chopped parsley before serving.