With a paring knife, lay each pepper flat on its side and carefully slice an inverted triangle out of the top of the pepper and remove. With a small spoon, scoop out any ribs and seeds and set aside. Do this for all the peppers, some "boats" will be smaller than others.
In a small bowl, mix tomato, cucumber, red onion, olive oil, vinegar and salt. Stir to combine and set aside.
Pipe or spoon hummus into each pepper through the opening you cut out, leaving a little room at the top. Once all the boats are filled with hummus, carefully spoon the cucumber and tomato salad on top of each boat. Serve cold.
With the pieces of pepper that were removed to form the "boat" I like to slice them up and serve with other dips or on a veggie platter.