Cottage Pudding with Lemon Sauce

Ingredients
1/4 cup shortening
3/4 cup sugar
1 egg
2 cups flour
2 tsp baking powder
1/3 tsp salt
1 cup milk

Instructions
Cream shortening, gradually adding sugar then beating egg.
Sift flour, baking powder and salt.
Add them to the mixture
Pour into rectangular cake pan - guessing 12X13, but there isn't a note.
Bake 350 for 30 minutes.

Lemon Sauce
1 cup boiling water
4 tbsp sugar
2 tbsp corn starch
2 tbsp butter
2 tbsp lemon (she always added a little more to taste)
Bring water to a boil and add cornstarch until moistened with a little cold water stirring while cooking
Cook for 3 minutes and then add lemon juice and butter