Directions

1. In a small heavy saucepan, mix sugar, cornstarch and salt. Whisk in milk. Cook and stir over medium heat until thickened and bubbly. Reduce heat to low; cook and stir 2 minutes longer. Remove from heat.
2. In a large bowl, whisk a small amount of hot mixture into egg yolk; return all to pan, whisking constantly. Bring to a gentle boil; cook and stir 2 minutes. Remove from heat. Stir in lemon juice, butter and lemon zest. Cool 15 minutes, stirring occasionally.
3. Transfer to four dessert dishes. Press plastic wrap onto surface of pudding. Refrigerate until cold, about 2 hours.
4. If desired, top puddings with sweetened whipped cream, lemon slices, and mint leaves just before serving.