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I recently watched the romantic drama The Taste of Things, in which there is much ado about a baked Alaska. This delicacy consists of sponge cake topped with a dome of ice cream, all of which is slathered with meringue that turns a gorgeous brown when cooked. The film’s characters briefly muse over the science involved in keeping ice cream from melting within a cake as it is baked in the oven. As many of us are approaching school holidays, I would say this is also an easy, delicious experiment you can conduct with any restless children.

There are two things that are particularly fun about this cake. First is that you can really go to town on the ice cream filling, designing your own version, whether that is colourful layers of flavoured ice cream, adding fresh or frozen fruit, or a classic vanilla.

The second is, of course, the wonderful effect of cooking ice cream without it melting. The explanation for how this is possible is, as with so many things in baking, to do with eggs. As these are whisked to make the meringue, the proteins stretch and trap air bubbles within. As air is a poor conductor of heat, the bubbles in both the meringue and the cake below act as insulators, protecting the ice cream from the oven’s heat.

To guarantee success, you need to get technical. The factors that will ensure your ice cream stays cold include the thickness of the sponge and meringue, as well as the temperatures of your oven and your ice cream. Luckily, this important scientific question has been investigated, and to bake the dessert at 200°C (400°F), you need to slather your meringue to at least 2 centimetres thick to ensure the ice cream doesn’t melt.

First, let’s deal with the filling. Scoop slightly soft ice cream into a bowl lined with aluminium foil or plastic wrap, then cover it and put in the freezer until set (at least 5 hours). The base of the cake is traditionally a vanilla sponge, but again you can go wild and pick whatever type of cake you like. I’ll leave that up to you. Ensure your sponge is at least 2.5 centimetres thick and cut it to match the size of the base of your ice cream dome.

Now for the meringue. Whisk the egg whites in a clean bowl, then add the dry ingredients (you can read my guide to perfect egg whites in my 11 May column).

When your ice cream, sponge cake and meringue are ready, it is time to assemble them. Remove the ice cream dome from your mould and put it on top of the cooled sponge, adding a layer of jam between the two if you like. Do all this quickly, on a baking tray lined with baking paper – as the ice cream needs to remain as cold as possible. Then spread the meringue over the top with a palette knife. Pop the assembled dessert into an oven preheated to 200°c/400°F, and bake for 8 to 10 minutes until golden brown. Serve quickly, to the delight of your guests/children.

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