Season the salmon: In a small bowl, combine the smoked paprika, garlic powder, salt, and black pepper. Rub the mixture evenly over each salmon fillet.
Sear the salmon: Heat the olive oil in a large skillet over medium heat. Add the salmon fillets and sear for 3–4 minutes per side, until golden brown. Remove from the skillet and set aside.
Sauté the aromatics: Add the butter to the same skillet. Once melted, add the diced onion and cook for 2 minutes until it softens. Stir in the garlic and cook for 1 minute more, just until fragrant.
Toast the orzo: Stir in the uncooked orzo and toast for 1–2 minutes, stirring frequently.
Cook the orzo: Pour in the chicken stock, season with chili flakes (if using), salt, and black pepper. Stir well, bring to a boil, then reduce heat to medium-low. Simmer for 6–10 minutes, stirring occasionally, until the orzo is tender and most of the liquid has been absorbed.
Make it creamy: Add the half-and-half (or heavy cream), frozen peas, shredded kale, and lemon juice. Cook, stirring often, until the kale wilts and the orzo becomes creamy. Taste and adjust seasoning if needed.
Return the salmon fillets to the skillet. Let it warm through on medium heat.
Sprinkle with freshly chopped parsley and serve with an extra squeeze of lemon if desired.