The rich pleasures of millionaire’s shortbread

When I was at university, there was a cafe nearby that made the millionaire’s shortbread of dreams: slabs as big as your hand, with soft caramel that only just held its shape, and would yield when bitten into; a thick layer of chocolate, and a base that somehow defied physics by being impossible crumbly and yet offering the structural integrity required for the top two layers. My waistline and student bank balance suffered accordingly, but these treats saw me through finals and essays, hangovers and heartbreak, rain and shine.

It’s not surprising that millionaire’s shortbread tends to be a hit with almost everyone: it combines three crowd-pleasers into pleasing layers in a portable square, perfect for parties and picnics (or the privacy of your student digs). Its name is supposed to have Scottish roots – although the caramel shortbread has its origins in the Australian Women’s Weekly – and refers to the richness of ingredients and elements. Richness therefore comes with the territory, and if that doesn’t appeal, this probably isn’t the bake for you. But if it’s the sweetness putting you off, try a small pinch of coarse salt in your caramel, as well as salted butter in your shortbread, just to take the edge of the sugar levels.

The required amount of condensed milk is half a standard single tin, so I often make a double batch and pop one in the freezer, where it will sit quite happily, tightly wrapped for up to three months. Allow to defrost completely before consuming.

Makes 12 squares

Takes 30 minutes, plus cooling

Bakes 30 minutes

For the shortbread base

75g caster sugar

175g plain flour

110g salted butter

For the caramel filling

75g salted butter

75g light brown sugar

200g condensed milk

½ tsp coarse salt

For the chocolate topping

100g milk chocolate

1. Preheat oven to 160°C. Line a square 8-inch baking tin with a strip of baking paper that overhangs the size of the tin (you can use these as handles later on).

2. First, make the shortbread. Rub together the caster sugar, flour and salted butter until it looks like breadcrumbs.

3. Press down into the tin with your fingertips, right into the corners, then compact the mixture so that it has a smooth top with the back of a spoon.

4. Bake for 30 minutes until golden. Remove, and allow to cool completely – it will still be very soft, but don’t worry, and don’t touch the baking paper handles.

5. Now, make the caramel: melt the soft brown sugar and second lot of butter together on a low heat, stirring occasionally, to prevent it from burning. When completely smooth, add the condensed milk and bring up to a gentle blipping boil. Cook for just one more minute (set a timer!), and then stir in the salt and pour on to the cool shortbread. Tipping the tin, or nudging a little with a spatula, should ensure you end up with a caramel layer which reaches right to the corners.

7. When the caramel has completely cooled, melt the chocolate over a bain marie and pour on top of the caramel layer, smoothing to the very edges with the help of a spatula or spoon. Leave to completely cool.

8. Run a hot knife round the edge of the tin to release the millionaire’s shortbread, using the baking paper as handles. Cut into 12 pieces. If you’d like precise edges to your squares, heat the knife briefly on the hob, or under hot water (don’t forget to dry it!) before cutting; wipe the knife on a slightly damp dishcloth between each cut.