Put the milk, lemon zest and cinnamon bark in a pot.  Bring to a boil, then put the fire off and let the lemon zest and cinnamon infuse the milk for 30 to 60 minutes.  Then sieve the mixture.

In a separate bowl, whisk together the egg yolks, sugar and corn starch until white and fluffy.

Put the egg yolk mixture on the fire and slowly add the milk, while whisking constantly.

Cook on a medium flame until it boils and the cream thickens.  It will be quite frothy at the beginning, but the foam will disappear once it starts to boil (at this point, the crema catalana will be ready).

Divide the cream between 8 ramekins and let it cool down. When at room temperature, put it in the fridge until you are ready to serve it.

Just before serving, sprinkle ½ tablespoon of sugar on each crema catalana and brûlée it using a torch.

Serve immediately.