Preheat your oven to 350°F (175°C). Line a large baking sheet with parchment paper. Keep aside.
Drizzle the salmon filets with 1 tablespoon of oil, then season with salt, pepper, smoked paprika and Cajun seasoning on both sides. Cut a slit through the middle of each salmon fillet, but not all the way through, about two-thirds of its total length. Keep aside.
Squeeze excess liquid out of the spinach and discard it.
In a medium bowl, combine the spinach with Boursin cheese, jalapeno, crab meat, parmesan cheese, and garlic. Season with salt and pepper to taste. Keep aside.
Put the shrimp in a medium-sized bowl. Add the remaining 1 tablespoon of oil, Cajun seasoning, smoked paprika, salt, and pepper. Mix everything together. Keep aside.
Stuff the salmon fillets with the crab mixture, and top with the seasoned shrimp. Transfer on the prepared baking sheet and pour the cajun butter over the salmon.
Bake for 15-17 minutes or until salmon is cooked through, opaque in center and flakes easily with fork.
Serve with lemon wedges.
Enjoy!