For sauce, to food processor or blender container, add yogurt, feta, lemon juice, and dill; blend until smooth. Remove sauce from container and set aside. Clean container.
For burgers, in food processor container, place salmon, egg, almond flour, sun-dried tomatoes, shallot, jalapeno, capers (if using), lemon zest, salt, and black pepper; pulse several times until you have a chunky paste. Form salmon mixture into 4 equal-sized patties. Refrigerate patties for at least 15 minutes.
In skillet over medium-high, heat oil. Place salmon burgers in skillet and cook for about 3 minutes on each side, or until crispy on the outside but just barely cooked through in the middle. The thickest part of the burgers should reach 145 F when tested with a food thermometer.
Place burgers on bottom halves of buns and top with feta sauce, tomato, cucumber, and greens. Top with more sauce and place tops of buns on burgers.
Recipe Notes
Per serving: 589 calories; 46 g protein; 32 g total fat (9 g sat. fat); 28 g total carbohydrates (7 g sugars, 2 g fiber); 679 mg sodium