There is nothing remotely healthy, money-saving or worthy about today's recipe, so would those of a puritan disposition please go straight to the arts pages.

I had a birthday recently, and among the cards was one from a friend in Vermont depicting a tres leches cake. Unusually, it wasn't a photograph but a painting. With a feathered outline from the creamy frosting and a simple garnish of berry fruits scattered on and around it, the cake looked irresistible.

The card inspired me to search out tres leches cakes, as I really wanted one! Daft, I know, but I had got this bee in my bonnet. To begin with, I was looking for bakeries, but didn’t find any nearby. However, I did discover one in the area near Elephant and Castle known as Little Colombia. I remembered cakes like this when Tom and I were in Bogota and Quito, and in the many cafeterias in Miami's Little Havana.

In the end I decided to make one. My oven, in fact the whole kitchen, is on life-support, (appliances worn out after nearly 25 years) so I shall not be baking anytime soon. (A new oven? Well, the way that energy prices are rising, I might not bother) I bought, shock! horror! a ready-made sponge cake and proceeded from there.

If you were using my ice cream recipe earlier in the summer, you might well have some of the ingredients in your cupboard, evaporated milk and condensed milk. These are two of the tres leches. There is some disagreement about the third milk; does it refer to the whipped cream frosting, or simply to extra milk added to the above?

Since it is a flexible recipe, I also used another of my ice cream ingredients, a dollop of fresh custard when I opened up the sponge cake to scrape off the jam and butter cream, and sandwiched it together again. And after I had made the cake, I still had custard, condensed milk and evaporated milk left over, into which I stirred a triple shot of espresso and made a coffee ice cream.

Ideally, the cake recipe should be made with a fatless sponge, as this will more readily absorb the various liquids. It can be baked as free-standing cake or as a tray bake, and the soaking procedure begins about ten minutes after the cake comes out of the oven. With my bought cake, I warmed it in the microwave for 10 seconds beforehand.

Rather than soft fruit and berries for garnish, I like the traditional sprinkling of powdered cinnamon, which I forgot to add when I photographed the cake, but remembered before serving. This custardy, pudding-like cake has become a favourite overnight. Perfect for special occasions.

Frances's Tres Leches Cake (Serves 4)

Ingredients:

1 sponge cake - ideally a fatless sponge, which is more absorbent than a Victoria sponge recipe

Dollop of custard - optional

150 ml evaporated milk

150 ml condensed milk

200 ml double cream or whipping cream

Cinnamon - see recipe

Berry fruits

Method:

While the cake is still warm and on its cake rack, place it over a deep plate to catch any excess liquid.

If you have a bought, filled cake, split it open and scrape off the filling, as yours will be much better. Add a dollop of vanilla custard and put the cake back together again. Prick it all over with a skewer, pushed well into the cake. Mix the two milks and pour about a third of the mixture carefully and slowly over the cake. Leave it for 10 minutes, then slowly add a further third, also spooning over the cake any drippings. After another 10 minutes slowly pour the remaining mixture over the cake, again spooning up any drippings.

At this point, you can refrigerate the cake until required, up to 24 hours, and then spread on the whipped cream. Or if you want the cake within 5 or 6 hours, whip the cream and use to frost the cake.

When ready to serve, transfer to a suitable plate and decorate as you wish.

Cook's notes: the liquid volumes are based on a small cake, 15 cm diameter. For larger cakes and tray bakes, increase the amount of liquid. Essentially, just keep adding the liquid until the cake is saturated

If whipped cream is too rich for you, the cake, because it is moist, not to mention sticky, will happily take a generous scattering of good desiccated coconut.