In a large bowl, mix salmon, red onion, red bell pepper, zucchini, 1/4 cup dill, paprika, 1 teaspoon garlic powder, eggs, and flour. Divide evenly into fourths and for into 4 burger patties, each about 3/4-inch thick. Place patties on the baking sheet.
3 Bake burger patties for 20 minutes, until golden brown and cooked through.
4 In the meantime, make the yogurt mustard cream sauce. In a small bowl, combine yogurt, mustard, lemon juice, the remaining tablespoon of dill and the remaining 1/2 teaspoon garlic powder. Set aside.
5 Once salmon burger patties are cooked, add to toasted burger buns along with sauce, tomato, and arugula.