Lovely Lemon Pudding Cake

I made a Lemon Pudding Cake to continue my new year resolution to make different antique cakes. The recipe comes from Gourmet's Menu Cookbook, compiled and edited in 1963. Other versions online come from family recipes passed through many generations. One neat idea I saw was to make individual portions in ramekins and top with fresh fruit. This dish is not very sweet and does not rise. It's different and interesting!

Ingredients:
1 1/2 tbsp butter
3/4 cup sugar
2 tsp grated lemon zest
3 egg yolks
3 egg whites
3 tbsp flour
1/4 cup lemon juice
1 cup milk

Cream 1 1/2 tbsp butter with 3/4 cup sugar until the mixture is light and fluffy and beat in 2 tsps grated lemon zest. Add 3 egg yolks and beat well. Stir in 3 tbsps flour alternately with 1/4 cup lemon juice and 1 cup milk. Fold in 3 egg whites, stiffly beaten with a pinch of salt. Turn the batter into a buttered casserole, set the casserole in a pan of hot water, and bake the cake in a moderate oven (350 F) for about 1 hour, until the cake tests done on top. The bottom of the casserole will contain a think, lemony sauce.