Add the milk, cream and vanilla paste to a pan. Cut a thin strip of peel from the lemon, add to the pan, bring to the boil, allow to infuse for approx. 15 mins. Beat the eggs, sugar and cornflour. Remove the lemon peel from the milk, add the egg mixture, bring to the boil over a medium heat, stirring constantly. As soon as the mixture thickens, remove the pan from the heat and continue to stir for approx. 2 mins. Pass the crème through a sieve, divide between the ramekins, cover and chill for approx. 3 hrs.
Sprinkle sugar over the crème and caramelize with a blowtorch.