asian meatball subs with hoisin mayonnaise

Ingredients

• 1 slice white sandwich bread
• 1 1/2 tablespoons milk
• 1 teaspoon soy sauce
• 5 - scallions, white and green, parts seperated
• 1 1/4 pounds ground pork
• 3 large garlic cloves, finely grated
• 1 tablespoon ginger, peeled and finely grated (about a 2 inch piece)
• 1/3 cup water chestnuts, drained, rinsed, and chopped
• 1 large egg, lightly beatened
• 1/3 cup cilantro, fresh, chopped
• 1 1/2 teaspoons toasted sesame oil
• - kosher salt and freshly ground pepper
• 1/2 cup hoisin sauce
• 1/4 cup mayonnaise
• 2 1/2 tablespoons fresh lime juice
• 4 tablespoons asian chili-garlic sauce
• - peanut or vegetable oil, for frying
• 1 cup bean sprouts
• 4 - 7-inch-long pieces baguette, split open