Preheat oven to 375°F (190°C). Line a baking sheet with parchment paper or lightly grease.
Using a sharp knife, carefully cut a slit along the side of each salmon fillet to create a pocket (do not cut all the way through).
In a small bowl, mix spinach-artichoke dip, sun-dried tomatoes, and feta until combined.
Stuff each salmon fillet with the mixture and place them on the prepared baking sheet.
Bake for 18–22 minutes, until salmon flakes easily with a fork and filling is heated through.
Serve warm with a side of roasted vegetables, rice, or a fresh salad.