Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.

Slice each salmon fillet lengthwise to create a pocket, rinse, and pat dry.

Brush the salmon on both sides with olive oil and sprinkle with salt and pepper.

In a medium pan, heat remaining olive oil and sauté spinach with seasonings until wilted.

Turn off heat and fold in roasted red peppers, feta, and parmesan into the spinach mixture.

Stuff the salmon pockets generously with the spinach-feta mixture and place on the baking sheet.

Bake in the preheated oven for 12-17 minutes until salmon is opaque and cooked through.

Let the salmon rest for a couple of minutes before serving warm.