Thai Curry Paste Pulled Pork Sandwiches

Name: Thai Curry Paste Pulled Pork Sandwiches
Ingredients: 1/3 cup Thai red curry paste; 1/4 cup fish sauce; 6 tablespoons finely grated palm sugar or dark brown sugar; One 4-pound boneless pork shoulder roast with fat cap; Kosher salt; Pepper; 2 cups chopped cilantro stems; 4 garlic cloves; 2 large shallots, halved; 2 makrut lime leaves; 1 Thai bird chile; 1 stalk of fresh lemongrass, inner light green and white parts only, cut into 3 pieces; One 1/2-inch piece of fresh ginger, peeled and thinly sliced; 24 cardamom seeds; 1 1/2 teaspoons ground turmeric; One 15-ounce can unsweetened coconut milk, chilled; 1/3 cup chicken stock or low-sodium broth; 1/2 cup each finely chopped cilantro, Thai basil and mint leaves; Mayonnaise, for spreading; 8 brioche buns, split and toasted; Thinly sliced cucumber and red onion, cilantro, Thai basil and lime wedges, for serving