Preheat the oven to 400F and line a baking sheet with parchment. Toss the halved baby potatoes with olive oil, salt, pepper and garlic powder and spread on the sheet.
In a food processor, pulse the spinach, breadcrumbs, green onion, dill, feta, salt, pepper and garlic until combined but not over-mixed. Add the shrimp and pulse a few times.
Cut into the middle of the salmon filet about half an inch deep, then cut at an angle and gently open the sides to make a pocket. Spread the filling to the edges and fold the sides back over.
Roast the potatoes for 10 minutes, then push them to the sides of the pan.
Place the stuffed salmon in the center, drizzle with olive oil and top with lemon rounds. Bake 18-20 minutes, until the filling is cooked through.
Slice the salmon and serve with the potatoes, garnished with fresh dill.
