• Preheat the oven to 180℃ fan/200℃/Gas Mark 6. Grease the 7" cake tins with butter and line the bases with baking paper.
• Cream the butter and sugar until pale, light and fluffy with a handheld electric whisk (if you have one) or a wooden spoon. Stir in the Biscoff spread, followed by the eggs, one at a time, beating well after each addition. Don't worry if it starts to look a bit curdled, it'll all come together.
• Add the flour. If you've been using an electric whisk, do this with a wooden spoon.
• Divide the batter evenly between the prepared tins and smooth out with the back of a spoon. Make a bit of a dip in the middle of each sponge to account for rising, to help keep them level.
• Bake in the oven for about 25-35 minutes, or until a skewer inserted into the cakes comes out clean.
• Remove from the oven and allow the cakes to cool in the tins for about 5 minutes, then remove the tins and allow to cool completely on a wire rack.

To make the Biscoff Buttercream Icing:

• Beat the butter in a bowl until pale, light and fluffy (using an electric hand whisk if you have one).
• Gradually sift in the icing sugar and stir in the Biscoff spread. Beat in a little boiling water (2-3 tsps) to soften and lighten the texture of the icing. It should be light and fluffy.
• When your cakes are completely cold, sandwich together with half of the buttercream (using a piping bag if you have one). Spread or pipe the remaining icing on top before serving.