In a small bowl, whisk the oil vinegar, mustard, onion powder and a sprinkle of salt and pepper. Set aside.
MAKE THE SALAD:
To a small saucepan, add the potatoes and cover the water. Bring to a boil. Reduce the heat; cover and simmer until tender, 15 to 20 minutes. Drain and cool; cut into quarters.
Place the beans in another saucepan and cover with water. Bring to a boil. Cover and cook until crisp-tender, 3 to 5 minutes; drain and rinse in cold water.
Divide the lettuce between 2 salad plates; top with the potatoes, beans, tomatoes, olives, eggs and salmon. Drizzle the salads with the dressing, and serve.