Bring water to a boil in a pot, add salt, the cleaned green beans and after 2 min.
the broad beans. After another 2 min.
add the peas to the pot and cook the whole thing for 5 min. Drain the vegetables and quench them in ice water. Wash and chop the basil. Peel the onions and cut them into rings. In a bowl, mix 2 tablespoons of olive oil, 1 tablespoon of red wine vinegar and 1 pinch of salt to make a dressing.
To do this, dissolve the salt in the vinegar, then pour in the oil and whisk thoroughly to combine. Put the vegetables in a bowl, add the onion and basil, mix with the vinaigrette and serve.