Mix the sugar and eggs in a saucepan on the stove. Add salt, cornstarch and milk. Bring the mixture to a boil over medium heat, stirring constantly.
Simmer the mixture until it thickens (about 12 minutes). Remove the saucepan from the heat and add the vanilla extract, stir well.
Layer the vanilla biscuits, banana slices, and pudding alternately in a serving bowl. Finish with pudding. Place the bowl in the refrigerator for 4 hours, then serve.