01 - Combine heavy cream and sugar in a medium saucepan over medium heat. Stir gently until sugar completely dissolves.
02 - Bring mixture to a gentle boil, then reduce heat and simmer for exactly 3 minutes. Stir occasionally to prevent sticking or overflow.
03 - Remove from heat. Stir in lemon zest and fresh juice until thoroughly incorporated.
04 - Let mixture cool for 5 minutes. For ultra-smooth texture, strain through fine sieve into a pouring vessel. Divide evenly among 4 serving glasses or ramekins.
05 - Refrigerate for at least 3 hours until completely firm and set.
06 - Top with fresh berries and mint leaves immediately before serving.