Preheat your oven to 400°F (205°C) with the middle oven rack positioned. Line a heavy-gauge baking sheet with unbleached parchment paper.

Pat the salmon fillets completely dry with paper towels on both sides—dry fish ensures maximum crust adhesion and crisp skin. Arrange fillets skin-side down on the lined sheet. Brush top surfaces evenly with extra virgin olive oil, season with kosher salt and black pepper, then spread a thin layer of smooth Dijon mustard across each fillet.

In a medium mixing bowl, toss together the coarse panko breadcrumbs, freshly grated Parmigiano-Reggiano, minced garlic, melted butter, chopped parsley, lemon zest, garlic powder, and red pepper flakes until the crumbs resemble moist, clumpy sand.

Generously spoon the parmesan crumb mixture over each fillet, pressing gently with fingertips or an offset spatula so the crust adheres firmly in a solid layer. Bake at 400°F (205°C) for 10 to 12 minutes until the salmon is tender and flakes easily with a fork.

For an intensely crunchy, bubbly golden crust, switch the oven to high broil for the final 60 to 90 seconds. Watch closely through the oven window to prevent scorching! Transfer to warm dinner plates, squeeze fresh lemon juice over top, and serve immediately.