Prep the pan: Heat the oven to 425°F (220°C). Line a large sheet pan with parchment for easy cleanup.
Season the zucchini: Toss the zucchini with 1 tablespoon olive oil, a pinch of salt, and pepper.
Spread in a single layer over two-thirds of the pan so they roast, not steam.
Place the salmon: Pat the salmon dry and set the fillets on the remaining space on the pan. Drizzle with the remaining 1 tablespoon olive oil and season with salt, pepper, and the smoked paprika.
Make the topping: In a small bowl, mix melted butter, minced garlic, Parmesan, panko, parsley, lemon zest, and Italian seasoning. Stir until it resembles moist crumbs.
Top the salmon: Press the mixture evenly over the salmon fillets, packing it gently so it adheres.
Don’t worry if some falls onto the pan—those bits get deliciously toasty.
Roast: Bake for 10–12 minutes, until the zucchini edges are golden and the salmon is mostly opaque. For a deeper crust, switch to broil for 1–2 minutes at the end, watching closely.
Finish with lemon: Remove from the oven and squeeze lemon juice over the salmon and zucchini. Add a sprinkle of fresh parsley.
Serve: Plate with extra Parmesan if you like, plus lemon wedges on the side.
Pair with rice, crusty bread, or a light salad.