Adding olives can make tuna or salmon salad more interesting, as can sliced avocado or chopped hard-boiled egg. A slice of tomato on top of the tuna salad followed by a slice of cheese makes a great open-faced sandwich when broiled lightly to melt the cheese. You can also squeeze a fresh lemon over your salmon salad right before serving for added garnish and flavor, and use fresh ground pepper to complete the dish