In a large bowl whisk eggs, 2 teaspoons Dijon mustard, and horseradish. Stir in panko, onions and celery until mixed. Gently stir in salmon; form into 3-inch patties.
Heat olive oil in a large nonstick skillet over medium-high. Working in batches cook salmon patties until golden on both sides, about 3 minutes per side.
Make dressing by whisking walnut oil, vinegar, salt and remaining Dijon mustard in a large bowl. Add mixed baby greens to bowl and toss to coat,
To serve, place baby greens onto 4 dinner plates, top with salmon patties and sprinkle raspberries over all.