Place the flour in a large bowl and make a well in the middle. Beat together the egg with the milk and 2 tablespoons of the sugar and slowly add to the flour mixing well with a small whisk or wooden spoon until you have a smooth batter. Stir in the lemon zest and aside for about 30 minutes.
When ready to make the pancakes, rub a 20cm frying pan with a little sunflower oil and heat over a medium heat. Add a small ladleful of batter, just enough to coat the base of the pan, then swirl around the pan quickly until it covers the base. Cook for a minute until lightly coloured underneath then using a palette knife, flip over and cook for a further minute. Tip out onto a plate and place the pan back on the hob and continue to make 9 more pancakes adding more sunflower oil if needed.
Heat the butter in a large frying pan and cook the apple slices over a gentle heat until starting to turn golden then add the remaining sugar and cinnamon and cook for a further 5 -8 minutes until golden and caramelised.
Fold each pancake in half then fold in half again to form a cone. Fill each with some of the sticky apples. Place two pancakes on a plate and serve with a spoonful of mascarpone cheese and drizzle over any pan juices.
Cook's tip: for babies, mash some of the cooked apples before you add the sugar and mix with a little mascarpone. Serve with strips of the cooked pancake.