Bo Luc Lac (Vietnamese Shaking Beef)

Ingredients

• 1 1/2 pounds beef sirloin or tenderloin, cut into 3/4"-inch cubes
• 1-2 tablespoons vegetable oil (as needed)
• 2 tablespoons oyster sauce
• 1 tablespoon soy sauce
• 1 tablespoon Maggi seasoning
• 1 tablespoon granulated sugar
• 1/2 tablespoon sesame oil
• 4 cloves garlic, minced
• 2 shallots, thinly sliced
• 2 heirloom tomatoes, sliced
• 2 bunches watercress, washed and trimmed of tough stems
• 1 small onion, thinly sliced
• 1 teaspoon freshly cracked black pepper
• 1/4 teaspoon kosher salt
• 2 limes, juiced