Ingredients

• 1 pound of beef tenderloin or any tender cut of beef
• 4 cloves garlic minced
• 10 shallots minced
• 1 tablespoons of fish sauce
• 1/2 tablespoon of sugar
• 1/4 teaspoon salt
• pinch of ground black pepper
• 1 tablespoon of olive oil
• 3 tablespoon of canola oil
  Garnish:
• 4 cups of cleaned trimmed watercress or Boston lettuce leaves
• 2 medium sweet onions thinly sliced
• 2 teaspoons of vinegar + 1 teaspoon of fish sauce + 1 tablespoon of sugar

Preparations

• Cut the beef into 1-inch cubes. Marinate the beef in fish sauce, sugar, garlic, shallots, salt, black pepper and  olive oil. Mix 2 teaspoons of vinegar, 1 teaspoon of fish sauce, and 1 tablespoon of sugar; then pour over the slices of onion to make an onion pickle.
  
  Set aside
• In a skillet or non-stick frying pan heat the canola oil.  Under high heat add the meat, shake the frying pan to brown the outside of the cubes, and fry the meat for 4-5 minutes until it's medium rare.
  
  Season to taste
• Serve the beef on a platter of prepared watercress topped with the pickled onions.