Set your oven to 400°F (200°C). This temperature ensures the salmon roasts quickly and develops a lovely crust without drying out.
In a mixing bowl, whisk together the olive oil, smoked paprika, garlic powder, onion powder, salt, and black pepper. This fragrant blend will coat the salmon and infuse it with smoky, savory flavor.
Pat the salmon fillets dry with paper towels to remove excess moisture. This helps the spice rub stick better. Place the fillets on the lined baking sheet and brush or spoon the paprika mixture evenly over each piece, making sure to cover all sides.
Lay thin lemon slices directly on top of each salmon fillet. As the salmon roasts, the lemon will soften and release bright citrus notes that complement the smoky paprika beautifully.
Transfer the baking sheet to the oven and roast for 12-15 minutes, depending on the thickness of your fillets. The salmon is done when it flakes easily with a fork and has an internal temperature of 145°F (63°C).
Remove the salmon from the oven and sprinkle freshly chopped parsley over the top for a burst of color and fresh herbal flavor. Serve immediately with your favorite sides.