1Select a lean piece of Flank Marinating Steak as evenly flat as possible. Count 200 grams per person. Rub Cajun spices (Club House) and oil on both sides of the steak and let it stand on the counter for 20 minutes, tightly covered with plastic wrap (i.e. Stretch-and-Seal).
2In the meantime, pour 1 tbsp of oil in a cast iron pan and start warming it up slowly, increasing the heat a little at a time. When the pan is nearly red hot, cook the steak for 5 minutes on each side. Do not add salt. Set aside and cover with aluminum foil.
3After 15 minutes, using a very sharp knife, slice the steak against the grain, as thin as possible. Arrange on a plate with aragula salad, lemon quarters and caper vinaigrette on the side.
Soak 1 cup capers in cold water for 30 minutes. Drain and chop finely.
In a blender, process 1 tablespoon fresh lemon juice, 1 tablespoon sherry vinegar, 1 tablespoon cold-pressed olive oil, 1/2 teaspoon salt and ½ teaspoon black pepper.
Mix well, add chopped capers, then pour in a small serving bowl.