Pulled pork and apple rolls

Ingredients

• 2 1/2 -3kg pork shoulder, scored
• 1 tablespoon olive oil
• 1 tablespoon flaky sea salt
• 2 teaspoons garlic powder
• 2 teaspoons lightly toasted crushed fennel seeds
• 1 large onion, peeled, cut into 3 rounds
• juice of 1 lemon
• 1 crisp red apple, cored, cut into thin wedges
• 1 teaspoon butter
• pinch chilli flakes
• fresh rolls or sandwich bread
• 1/2 cup onion marmalade
• handful of rocket leaves