Roasted Pork Banh Mi

Ingredients

• ¼ cup mayonnaise
• 1 tablespoon asian fish sauce
• 1 teaspoon ground coriander
• 1 tablespoon each of whole white and black peppercorns
• .75 cup plus 2 tablespoons kosher salt
• ½ light brown sugar, packed
• 6 serrano chiles, crushed
• 10 cloves garlic cloves, peeled and minced
• 6 jalapeños, thinly sliced
• 2 slices warm water
• 1 (3‑pound) boneless pork shoulder (also called “buttâ€)
• 6 cups cold water
• ½ cup distilled white vinegar
• ½ cup granulated sugar
• ½ teaspoon kosher salt
• 1½ cup coarsely shredded carrots (about 6 carrots)
• 2 long baguettes, split lengthwise, centers slightly hollowed out
• 1 seedless cucumber, halved crosswise and thinly sliced lengthwise
• 1 cup cilantro leaves
• 2 tablespoons additional asian fish sauce
• 1 tablespoon soy sauce
• hot sauce, for serving (optional)