Bring cream and sugar to boil over a medium-high heat, stirring until sugar dissolves. Reduce heat to medium, and boil 3 minutes, stirring constantly, adjusting heat as needed to prevent mixture from boiling over. Remove from heat.
Stir in lemon juice and zest and let sit for 10 minutes to cool.
Stir mixture again and divide among six ramekins or glasses.
Cover each ramekin with plastic wrap and chill until set, 1 hour or overnight.
Allow to set completely before garnishing Garnish with fresh berries or mint.