Place a large pot filled with water on high fire. Cover and when it comes to a boil add the courgettes and the potatoes. Cook the courgettes for about 15’, to soften a bit, and the potatoes for an extra 10’. Remove from the pot and allow to cool.

Once cool enough to handle, cut the courgettes into thick slices, peel the potatoes and cut them the same size chunks as the courgettes.

In another small pot filled with water add the eggs, bring to a boil and cook for 8’. Remove from the pot and allow to cool.

Make the dressing by add into a bowl the mustard along with the oregano, vinegar, salt and pepper. Slowly drizzle the oil while whisking.

To assemble the salad, use a flat plate and add the courgettes with the potatoes, tomatoes, capers, scallions, optionally the olives and the parsley. Pour the dressing and fold gently. Finally add the eggs and serve.