Bake cake according to the box. When done poke holes in the with the end of a wooden spoon.

In saucepan combine sugar and lemon juice until sugar is melted. Mix 2 tbsp cornstarch and 1/4 cup of water in separate bowl until well blended. Slowly add cornstarch to lemon mixture until thickened to the consistency of gravy. Pour over the top of the cake

Note: it would also be good to add Strawberry's to the topping.