Zest a lemon over a bowl and set aside for the cupcakes. Then juice the lemon for the lemon cream.
We added a few drops of yellow food colouring to give the lemon cream a yellow hue, as if it was made with egg yolks. Without the food colouring, the lemon cream will be more white than yellow but will taste just as good.
To preplace the buttermilk, add 1 1/2 tsp (7.5 ml) white vinegar or lemon juice to 1/2 cup (125 ml) milk. Let sit for 5 to 10 minutes before stirring.
When caramelizing white chocolate, it tends to become grainy. But don’t worry, this is perfectly normal. Caramelized white chocolate, sometimes called blond chocolate, is available in some grocery stores and specialty shops.