For the filling

1. Heat the oil in a small skillet or saucepan on medium-low heat and swirl to coat evenly. Once the oil is hot, add the ground cardamom and ginger and cook for 30 seconds. Stir in the coconut and occasionally cook to prevent the coconut from sticking for about 2 minutes. Then stir in the jaggery, cook with constant stirring, and cook for 5 to 6 minutes until most of the liquid evaporates. Transfer to a medium bowl and keep aside until ready to assemble the crepes.

For the crepes

1. In a large bowl, dry whisk the flour and salt. Then make a well in the center and add the egg and milk. Stir with a wooden spoon until there are no lumps and the batter is smooth with a consistency like that of a thin pancake batter. Cover the bowl with cling film and let it sit for at least 2 hours (you can make this overnight and refrigerate) to let any trapped air bubbles out.
2. Grease a small cast-iron, stainless-steel, or non-stick skillet with a little oil and heat on medium-high. Pour ¼ cup/60 ml of the batter into the center and tilt and rotate the skillet to spread the batter evenly in a very thin layer. Return to heat and cook for about 1 to 1 ½ minutes until lightly browned and the edges start to come away from the sides of the pan. Gently flip the crepe, as soon as it starts to come off from the sides. Cook for an additional 30 seconds and transfer to a plate. 
3. Take 2 generous tablespoons of the coconut-jaggery filling and place it in the center of the crepe in the shape of a small log. Fold the top and bottom edges of the crepe over the filling and then roll the longer end of the crepe to wrap the roll, tucking it snuggly as you move towards the end. Keep aside in a serving dish. Repeat to prepare the remaining crepes. Serve immediately or at room temperature. These crepes will be good for up to 3 days if refrigerated in an airtight container.