Vegetarian slow cooker corn chowder

Name: Vegetarian slow cooker corn chowder
Ingredients: 1-2 leeks (thinly sliced); 2 celery stalks (thinly sliced); 2 tbsp coconut oil; 1 tbsp curry powder; 1 tbsp salt flakes (plus extra to taste); 3 cups corn kernels (cobs reserved, see tips for using frozen); 6 medium-sized mashing potatoes (scrubbed and halved, see tips); 3-4 garlic cloves (bruised and peeled); Thumb's worth of fresh ginger (roughly chopped (optional)); 500 ml (2 cups) vegetable stock, see tips; 200 ml coconut cream (see tips); Juice of half a lime; 2 tbsp coconut oil for frying (optional); Salt flakes