When you want to cook something tasty and healthy but are short on time, the best option is to assemble dishes that do not have to go in the oven. This tuna salad without mayonnaise is low calorie and only takes 15 minutes to prepare. It’s a good, substantial meal - and delicious, of course. 



  • 1/2 medium red onion, thinly sliced 
  • 1/4 cup red vinegar 
  • Kosher salt and freshly ground black pepper 
  • 1 cup cherry tomatoes cut into halves or quarters, if large 
  • 1 large orange and 1 yellow pepper, chopped 
  • 2 avocados, chopped 
  • 2 cans of tuna, drained 
  • 1/4 cup olive oil 
  • 2 tablespoons Dijon mustard 
  • 2 tablespoons chopped chives 



1. Combine 1 onion, 2 tablespoons of vinegar and 3/4 teaspoon of salt in a medium bowl. Marinate for 20 minutes, stirring occasionally.  

2. Meanwhile, prepare the sauce. Mix the olive oil, mustard, the remaining 2 tablespoons of vinegar and 3/4 teaspoon of salt and pepper in a small bowl.  

3. Before serving, put the onions, tomatoes, peppers, avocado and tuna on a platter. Drizzle with the sauce and top with chives. Serve immediately.