Wilt, Dry & Chop the Spinach: Heat a pan on medium with a drizzle of oil, add spinach, and cook 1-2 minutes until wilted. Remove, let cool 30 seconds, press dry with paper towels, then chop finely.
Make the Filling: In a bowl, mix the spinach, Boursin cheese, lemon juice, Parmesan, and butter (optional) until thick and creamy, like whipped frosting.
Cut the Salmon Pocket: Lay salmon on its side, slide a knife into the center of the fillet edge, and cut inward (not through the other side). Open the pocket and spoon in the filling generously.
Sear on the Stove: Heat oil medium-high until shimmering. Add salmon and cook 3 minutes untouched, then flip gently and cook 2-3 minutes on the other side until golden with crisp edges.
Finish in the Oven: Bake at 400°F for 8-10 minutes, until the salmon flakes easily and is no longer dry.
Make the Potatoes: Boil water, remove from heat, add the Idahoan Roasted Garlic Protein+ potatoes, and stir until smooth. Add cream for extra silky texture if desired.
Optional Garlic Butter Drizzle: Melt butter, add garlic for 30 seconds, add cream and lemon, and simmer 1-2 minutes. Drizzle around the salmon (do not drown it).