How to Make It
In a mortar, puree the garlic with 1/4 teaspoon salt. Add the egg yolks and pound until smooth. Stir in the sherry vinegar and mustard and transfer to a small bowl. Slowly whisk in the oil and season with salt and pepper.
In a large bowl, combine the broccoflower, cauliflower, frisée, scallions, celery, cucumber, parsley, bell pepper, olives and capers. Add the dressing and toss well. Finely dice the egg whites, scatter them over the salad and serve.