Prepare the lemon shells

• Halve the lemons lengthways and scoop out the pulp, keeping the shells intact.
• Juice the reserved pulp to obtain the lemon juice.

Boil the cream and sugar

• Bring the cream and sugar to a boil in a small saucepan over medium-high heat, stirring until the sugar dissolves.
• Reduce the heat to medium and boil, stirring constantly and adjusting the heat to prevent it boiling over.

Add the lemon

• Remove the saucepan from the heat.
• Stir in the lemon juice and zest.
• Let the mixture sit to cool slightly.

Fill and chill

• Pour the mixture into the hollowed lemon halves.
• Set them on a cutting board or in a muffin pan.
• Refrigerate until set.

Optional brûlée topping

• Sprinkle a thin, even layer of sugar over the top of each posset.
• Caramelize the sugar with a kitchen blow torch.
• Serve immediately.