Mustard Soy Mayonnaise

• 2 star anise
• 1 walnut-size piece of fresh ginger, smashed with a cleaver or meat pounder
• 3 tablespoons soy sauce
• 1 tablespoon brown sugar
• 2 tablespoons rice wine vinegar or white vinegar
• 2 small garlic cloves, minced 2 egg
• ¼ cup Dijon mustard
• 1¼ cups peanut oil
• Salt and freshly ground pepper
• 2 flank steaks, about 1 pound each, or 2 pounds cooked Brisket of Beef, thinly sliced
• Olive oil as needed
• Salt and freshly ground pepper
• 12 to 16 slices of bread
• 12 to 14 romaine lettuce leaves, cut into small strips, or 24 small watercress sprigs, trimmed of thick stems
• 2 cucumbers, seeded, peeled (if not English), and thinly sliced

For the mayonnaise, make a soy infusion by bringing the star anise, ginger, soy sauce, sugar, vinegar, and garlic to a boil in a small saucepan. Reduce the heat and simmer for about 2 minutes. Strain the liquid and cool. Discard the anise and the ginger. Put the eggs in the bowl of a food processor. Add the mustard and process to blend. Then gradually process in the peanut oil to form a mayonnaise. Add the cooled soy infusion. Season to taste with salt and pepper. (If you like, you may simply stir the soy infusion into 1½ cups prepared mayonnaise.)

Preheat the broiler or make a charcoal fire. Brush the flank steaks with a little olive oil and sprinkle with salt and pepper. Grill until rare, about 3 minutes per side. Let cool and then thinly slice across the grain.

Spread mayonnaise generously over 1 side of each slice of bread. Cover half the bread slices with meat. Place the romaine or watercress on the remaining bread slices. Top with cucumbers. Assemble the sandwiches and cut each in half.