Lemon Posset U cant get simpler then this :) By Guest Contributor November 18, 2012 Dessert Preparation Time Cook Time Servings0Ingredients600ml double cream140g caster sugar2 large lemons for the juice and the zestInstructions Step 1: 1. Put the double cream in a large pan with the sugar. Let boil and simmer for 3 minutes. Take it off the heat, add the lemon juice and zest and whisk well. Step 2: Step 3: 2. Pour into 6 ramekins and refrigerate for 2-3 hours.