Ingredients
- 350g digestive biscuits
- 160g butter
- 6 whole eggs
- 230g caster sugar
- Zest of 6 lemons
- Juice of 6 lemons
- 120g cold butter, cubed
- Line a 20cm loose base square cake tin with parchment paper.
- Place the digestive biscuits in a plastic ziploc bag, removing as much air as possible from the bag before closing. Use a rolling pin to crush the biscuits to a crumb by rolling it back and forth over them and lightly bashing (can be done in batches). Then, pour all the crumbs into a large mixing bowl.
- Place the butter in a small saucepan and melt over a low heat, then add the melted butter to the digestive crumbs and mix with a wooden spoon until evenly combined. Spoon the crumb into the lined cake tin. Use the back of a metal spoon to compress the biscuit base down until it is smooth and even. Then set aside.
- Preheat the oven to 160 degrees. Add the eggs, sugar and lemon zest to a bowl and lightly whisk by hand to evenly combine. Add the lemon juice to the mix and whisk lightly until combined, then pour the mix into a medium-sized saucepan.
- Place the saucepan on a low heat and heat gently while stirring constantly until it thickens (this will take around five to eight minutes). As soon as it thickens, remove the saucepan from the heat. Continue stirring while adding in the cold butter, one cube at a time, until the butter has melted and been stirred through the mix.
- Pour the lemon curd mix on top of the biscuit base in the cake tin. Tap the tin gently to remove any air bubbles, then place the tin in the oven and bake for 15 minutes at 160 degrees.
- Remove from the oven (it should still have a little wobble in the centre) after 15 minutes and allow to cool to room temperature. Then cover and place in the fridge. Keep in the fridge overnight to set.
- Remove the lemon curd cake from the fridge. Lift it out of the tin and remove the parchment paper. Use a sharp knife to slice into fingers and serve.
