Preheat your oven to 400°F (200°C) to ensure it's nice and hot for that golden pastry finish.

In a skillet, heat a splash of olive oil over medium heat. Add minced garlic and sauté until fragrant, about 1 minute.

Toss in fresh spinach and stir until it wilts, which should take about 2-3 minutes. Remove from heat and allow to cool slightly.

In a mixing bowl, stir together the wilted spinach, cream cheese, feta, Parmesan, lemon juice, salt, and pepper until well blended.

Pat dry the salmon fillets with a paper towel. Season both sides lightly with salt and pepper before creating a pocket in the thickest part of each fillet.

Stuff the filling into the pockets of the salmon, then place the salmon in the center of rolled-out puff pastry.

Fold the pastry over the salmon, sealing the edges to keep that delicious filling in.

Place the wrapped salmon seam-side down on a parchment-lined baking sheet. Brush the top generously with an egg wash and bake for 25-30 minutes, until the pastry is golden brown and flaky.

Allow the Wellington to rest for 5 minutes after baking before slicing.