In a skillet over medium heat, add olive oil, then sauté the minced garlic until fragrant, about 1 minute.
Add the chopped spinach to the skillet and cook until wilted, about 2-3 minutes. Remove from heat.
In a mixing bowl, combine the sautéed spinach, crumbled feta cheese, softened cream cheese, and lemon juice. Mix well until thoroughly combined.
Using a sharp knife, cut a pocket in each salmon fillet by slicing horizontally through the thickest part, being careful not to cut all the way through.
Season the inside and outside of each salmon fillet with salt and pepper.
Stuff each salmon fillet with the spinach and feta mixture, pressing down gently to ensure it stays inside.
Place the stuffed salmon fillets in a greased baking dish.
Bake in the preheated oven for 20-25 minutes, or until the salmon is cooked through and flakes easily with a fork.
For a golden top, you can broil the fillets for an additional 2-3 minutes at the end of baking.
Remove from the oven, let rest for a couple of minutes, and garnish with fresh dill or parsley if desired.
Notes
For a golden top, broil the fillets for an additional 2-3 minutes at the end of baking.