In this light but filling lunch, canned tuna—our consummate pantry pal—is tossed with a punchy lemon-caper vinaigrette and served with a crisp side salad. Try this once and you won't miss the mayonnaise-heavy alternative one bit.
Place tuna in a bowl and flake with a fork. Add bell pepper, oil, lemon juice, mustard, capers, and parsley; stir well to combine and season with salt and pepper. Serve with salad greens, cucumbers, and crackers on the side.