Preheat oven to 350°F.

Grease two 8-by-2-inch round cake pans.

For the cake: Sift the flour, baking powder, baking soda and salt together into a bowl and set aside.

Cream the butter and sugar in a large bowl with an electric mixer at medium speed until light and fluffy, about 5 minutes.

Reduce the speed to medium-low.

Add the eggs, one at a time, beating 30 seconds between additions.

Add alternating increments of the flour mixture and buttermilk and vanilla, blending well after each addition; this should take about 3 to 5 minutes.

Divide the batter evenly between the prepared pans.

Bake for about 30 minutes, until a cake tester comes out clean.

Cool in pans, on wire racks, for 10 minutes, unmold the cakes and let cool completely.

Note: The cake recipe makes two 8-inch round cake layers.

Only one is used for this recipe.

To assemble cake: Cut the cake in half horizontally.

Place one layer on a cake plate, spread cake with cold custard cream and sprinkle with brittle crumbs.

Cover with the remaining layer of cake.

Spread the remaining custard cream over cake, applying a thinner coat to the sides than the top.

Chill for a least 1 hour before garnishing.

To garnish, press brittle crumbs onto the sides of the cake with the palm of your hand and sprinkle a layer of crumbs on the top.

Refrigerate until ready to use.