In a small bowl, whisk together all ingredients for the vinaigrette except for the olive oil. (Note: if you are using an aged balsamic, you may not need to add the brown sugar as it may already taste quite sweet.) While whisking briskly, add the olive oil in a steady stream and combine well until the dressing is emulsified.
Marinate and grill salmon filets - see the link in the notes section to my BEST GRILLED SALMON recipe.
Wash and trim asparagus. Toss with olive oil and season with salt and pepper. Grill over medium high heat for 3-4 minutes or until crisp tender, turning frequently. (Using a grill basket works well!)
Add salad greens to a large bowl. Top with tomatoes, grilled asparagus, and Feta cheese. Add grilled salmon and top with potato sticks.