Bring a medium pot of salted water to a boil. Add 8 oz of orzo pasta and cook according to package instructions, usually about 8–10 minutes, until al dente. Drain and set aside.
Pat salmon fillets dry and season both sides with 1 tsp Cajun seasoning, salt, and pepper. Heat 2 tbsp olive oil in a large skillet over medium-high heat. Once hot, add the salmon fillets skin-side down (if skin-on). Cook for about 4–5 minutes per side until golden brown and cooked through. Remove salmon from the pan and set aside.
In the same skillet, reduce heat to medium and add minced garlic. Sauté for about 30 seconds until fragrant, then add 2 cups fresh spinach. Stir until wilted, about 1–2 minutes.
Pour in 1 cup heavy cream and bring to a gentle simmer. Stir in 1/2 cup grated Parmesan cheese until melted and the sauce thickens slightly.
Add the cooked orzo and 1/4 cup chopped green onions to the skillet. Stir everything together until the orzo is well coated with the creamy sauce.
Plate a generous scoop of the creamy spinach orzo and top each portion with a Cajun salmon fillet. Garnish with extra green onions if desired and enjoy immediately.
