My boyfriend loves salad and does a lot of athletics, so he needs his salads to be hearty, filling affairs. This tuna-avocado number is luscious, with lots of varied flavors in each bite, and it's full of what nutritionists refer to as "good" fats: tuna, olive oil and avocado. I poach fresh tuna steaks in olive oil and keep them packed in jars in the fridge, but you could just as easily use oil-packed tuna from the store. —MissGinsu
In a large bowl, combine the lettuces, tomato halves, tuna chunks, avocado pieces, green onion slices and parsley.
In another bowl, whisk the balsamic vinegar, slowly pouring in the olive oil to create an emulsion. Season to taste with salt and pepper before drizzling the vinaigrette over the bowl of salad. Serve immediately.