Source: I got this recipe years ago in a Holiday Cookbook in the children's section of the library. I have made it many times. Love it.
I do not make the sponge cake recipe, but make a yellow or French vanilla cake from a mix. Then I make little sandwiches out of the cake, spreading the jam between two small pieces of the cake.
3 (10 ounce) packages frozen raspberries (I use only 1 bag)
Simple Sponge Cake (recipe follows)
Cream sherry (optional)
1 jar seedless raspberry jam
Vanilla Custard (recipe follows)
3/4 cup heavy cream
2 tablespoons granulated sugar
1/3 cup slivered almonds, toasted (I omit these)
Defrost the raspberries and put them in a large strainer set over a bowl. Let them drain for 30 minutes. Set aside 30 of the best-looking raspberries for decorating the trifle.
If the sponge cake is uneven on top, trim it flat. Split the cake in half horizontally to make two thin layers and brush the cut sides with sherry to moisten (not soak) them. Spread the cut sides with most of the jam; you may not need all the jam. Cut each layer in 25 squares.
Line the bottom of a two-quart glass bowl or other pretty bowl with one third of the cake squares, jam sides up. Arrange half of the remaining drained raspberries over the cake. Spread half of the vanilla custard over the raspberries. Repeat the process, making another layer of cake squares, raspberries and custard; you will have one third of the cake left over.
Top the custard with the remaining cake squares, jam sides down. Refrigerate until needed, but keep in mind that the longer the trifle stands, the more the layers merge and lose their distinct flavors and textures.
Just before serving, whip the cream with the sugar and spread about a third of it over the trifle. With the remaining whipped cream, pipe large rosettes or drop large spoonfuls around the edge of the trifle bowl. Decorate with the reserved raspberries and sprinkle with slivered almonds.
Simple Sponge Cake
3 eggs, room temperature
3/4 cup granulated sugar
Pinch of salt
1 teaspoon vanilla extract
3/4 cup cake flour mixed with 1/2 teaspoon baking powder
Preheat the oven to 350 degrees F. Grease the baking pan (8 x 8 x 1 1/2 inches), line the bottom and sides with wax paper and grease the wax paper.
Beat the eggs until frothy. Add the sugar, salt and vanilla and continue beating until thick and pale and tripled in volume.
Using a fine strainer, sift the dry ingredients over the egg mixture a little at a time, folding them in. Pour the batter into the prepared pan.
Bake for 30 minutes or until the top is golden and springs back when pressed lightly. Let the cake cool in the pan on a wire rack for 5 minutes and then turn out on the rack. Peel off the waxed paper and turn right side up to finish cooling on the rack.
1/2 cup granulated sugar
3 tablespoons cornstarch
2 cups milk
3 egg yolks
2 teaspoons vanilla extract
In a saucepan, stir together the sugar, salt and cornstarch. Gradually add the milk, whisking until the mixture is smooth. Stir in the egg yolks. Bring the mixture to a boil over medium heat and boil for one minute, stirring constantly. Remove from the heat and stir in the vanilla extract.
Strain into a bowl, cover the surface directly with plastic wrap and let the custard cool in the refrigerator.
I do not use the sherry. I like to put the trifle on the table with a bottle of brandy or sherry for people to add their own, if desired.