11. Preheat oven to 375 degrees f (190 C). Grease and flour three 9-inch round cake pans.
2. Cream butter and sugar together until light and creamy. Beat in vanilla.
3. Sift together flour, baking powder and salt twice. Stir flour mixture into batter alternately with milk.
4. Beat egg whites until stiff but not dry. Stir 1/4 of whites into batter. Fold in remaining whites until just mixed.
5. Spoon batter into the 3 prepared cake pans and bake 20 to 25 minutes. Cool in pans for 10 minutes; turn onto cake racks.
2while cooling make filling
36. To prepare filling, mix together yolks, sugar and orange rind in a heavy pan or in top of a double boiler.
7. Cook over medium heat, stirring constantly, until sugar dissolves and mixture thickens enough to coat back of spoon. Do not allow to boil or eggs will scramble.
8. Remove from heat and stir in remaining ingredients. Let filling cool. Fill the cake layers and spread on top and sides of cake.
4Lane cake improves in flavor as it ages and mellows. Covered and uncut, this cake can be made 1 week before serving. It's not necessary to refrigerate, I do put a little borubon in a spray bottle and spray it a couple times during the week.
5i did put prep min 1 1/2 due to all the chopping etc, the cake only takes 25 mins but add 20 mins or so for the cooking of filling.