To make the Sweet Mustard sauce, whisk together the mustard and honey in a small bowl. Slowly drizzle in the olive oil, whisking continuously. Stir in the lemon juice and season with salt and pepper.

To hard boil the egg, put the egg in a small pot and fill with water to cover the egg by 1-inch. Bring the water to boil and immediately turn the heat off. Let the eggs sit in the hot water for exactly 7 minutes. Drain, rinse under cool water and peel when cool enough to handle. Cut the egg into quarters, lengthwise.

Heat a grill pan over high heat. Brush salmon fillets with 2 tablespoons of the olive oil and grill for 2 minutes on each side.

Wipe the grill pan clean, brush the remaining 1 tablespoon olive oil on the bread and grill the bread for 30 seconds each side, until nicely toasted (or use a toaster)

To assemble sandwiches, first cut each piece of salmon into 2 pieces. Layering leafy greens, tomato, avocado, egg, red onion, grilled salmon and capers on each bread slice. Spoon the sweet mustard sauce on top and serve, opened faced.