1In a small saucepan, bring cream and sugar to a boil over medium-high heat, stirring until the sugar dissolves. Reduce heat to medium and boil for 3 minutes, stirring constantly. Adjust heat as needed to prevent boiling over. Remove from heat.
2Stir in lemon juice and zest and let sit for 5 minutes to cool.
3Pour the mixture into the halved lemons.
4Place them on a cutting board or cupcake pan and place them in the fridge to chill, at least 3 hours.
5To brûlée, add a teaspoon of sugar to the top in an even layer. With a kitchen blow torch, caramelize the top. Serve immediately.