Mince the onion and soak it in water, then drain.

Pat the salmon fillets dry with a paper towel and season with salt and pepper.

Prepare the tartare sauce by mashing the boiled eggs in a bowl with a fork, then mixing in the minced onion, mayonnaise, salt, and black pepper.

Place the salmon on a baking tray lined with aluminum foil. Top each fillet with tartare sauce and breadcrumbs, then drizzle with olive oil. Cover with aluminum foil and bake in a toaster oven for 12–15 minutes until the salmon is cooked through.