1. Center a rack in the oven and preheat the oven to 350 degrees F. Butter two 9 x 2 inch round cake pans and line the bottom of each pan with a round of buttered parchment or wax paper. Put the pans on a baking sheet.
2. To Make the Cake: Sift together the flour, baking powder and salt. Whisk together the milk and egg whites in a medium bowl. Put the sugar and lemon zest in a mixer bowl or another large bowl and rub them together with your fingers until the sugar is moist and fragrant. Add the butter and working with the paddle or whisk attachment, or with a hand mixer, beat at medium speed for a full 3 minutes, until the butter and sugar are very light. Beat in the extract, then add one third of the flour mixture, still beating on medium speed.
Beat in half of the milk-egg mixture, then beat in half of the remaining dry ingredients until incorporated. Add the rest of the milk and eggs beating until the batter is homogeneous, then add the last of the dry ingredients. Finally, give the batter a good 2- minute beating to ensure that it is thoroughly mixed and well aerated. Divide the batter between the two pans and smooth the tops with a rubber spatula. Bake for 30-35 minutes, or until the cakes are well risen and springy to the touch - a thin knife inserted into the centers should come out clean
Transfer the cakes to cooling racks and cool for about 5 minutes, then run a knife around the sides of the cakes, unfold them and peel off the paper liners. Invert and cool to room temperature, right side up (the cooled cake layers can be wrapped airtight and stored at room temperature overnight or frozen for up to two months).
3. To make the Orange Cream Cheese Frosting: In a medium mixing bowl combine cream cheese, butter and orange juice. Beat on low to medium until light and fluffy. Gradually add 4 cups powdered sugar, beating well. Gradually beat in the remaining powdered sugar until frosting reaches spreading consistency.
4. To Assemble the Cake: Using a sharp serrated knife and a gentle sawing motion, slice each layer horizontally in half. Put one layer cut side up on a cardboard cake round or a cake plate protected by strips of wax or parchment paper.
Spread it with one third of the preserves. Cover the jam evenly with about one quarter of the frosting. Top with another layer, spread with preserves and frosting and then do the same with a third layer (you'll have used all the jam and have frosting leftover). Place the last layer cut side down on top of the cake and use the remaining frosting to frost the sides and top.
Serving: The cake is ready to serve as soon as it is assembled, but I think it's best to let it sit and set for a couple of hours in a cool room - not the refrigerator. Whether you wait or slice and enjoy it immediately, the cake should be served at room temperature; it loses all its subtlety when it's cold. Depending on your audience you can serve the cake with just about anything from milk to sweet or bubbly wine.
Storing: The cake is best the day it is made, but you can refrigerate it, well covered, for up to two days. Bring it to room temperature before serving. If you want to freeze the cake, slide it into the freezer to set, then wrap it really well - it will keep for up to 2 months in the freezer; defrost it, still wrapped overnight in the refrigerator.