Alfajores: Argentine Dulce de Leche Sandwich Biscuits
Ingredients
- FOR THE DULCE DE LECHE:
- 1 litre whole milk
- 250g caster sugar
- ¼ teaspoon bicarbonate of soda
- 1 teaspoon vanilla extract
- FOR THE BISCUITS:
- 200g unsalted butter, softened
- 130g icing sugar, sifted
- 2 large egg yolks, at room temperature
- 1 large egg, at room temperature
- 1 teaspoon vanilla extract
- Finely grated zest of 1 lemon
- 350g plain flour
- 1 teaspoon baking powder
- ¼ teaspoon fine salt
- Icing sugar, for dusting
Instructions
- 1
MAKE THE DULCE DE LECHE:
- 2
Place the milk and sugar in a large, heavy-based saucepan. Heat gently, stirring until the sugar has completely dissolved.
- 3
Dissolve the bicarbonate of soda in 1 tablespoon of water, then carefully stir it into the milk. The mixture may foam, so ensure the pan is large enough to prevent it from overflowing.
- 4
Bring to a gentle simmer and cook uncovered over low heat for 1½–2 hours. Stir occasionally at first and more frequently as the mixture thickens and darkens.
- 5
Remove from the heat when it is deep caramel in colour and thick enough for a spoon drawn across the bottom of the pan to leave a visible trail for a few seconds. It will thicken further as it cools.
- 6
Stir in the vanilla, then transfer the dulce de leche to a heatproof bowl.
- 7
Cover the surface directly with cling film to prevent a skin from forming, then leave to cool completely before using.
- 8
MAKE THE BISCUITS:
- 9
Beat the softened butter and icing sugar until smooth, pale and creamy.
- 10
Add the egg yolks one at a time, mixing well after each addition. Add the whole egg, vanilla and lemon zest and mix until combined.
- 11
Sift the plain flour, baking powder and salt into a separate bowl.
- 12
Add the dry ingredients gradually to the butter mixture, mixing only until a soft dough forms.
- 13
Flatten the dough into a disc, wrap and refrigerate for 30–45 minutes, or until firm enough to roll.
- 14
Preheat the oven to 180°C conventional or 160°C fan. Line 2 baking trays with baking paper.
- 15
Roll the dough to a thickness of 6–7mm on a lightly floured surface. Cut out rounds with a 5cm cutter and arrange them on the prepared trays.
- 16
Gently bring the scraps together, reroll and cut out more rounds. If the dough becomes soft, refrigerate the cut biscuits for 10–15 minutes before baking.
- 17
Bake for 9–11 minutes, until set but still pale. Leave on the trays for 5 minutes before transferring carefully to a wire rack to cool completely.
- 18
Pipe or spoon a generous layer of cooled dulce de leche onto the flat side of half the biscuits. Top with the remaining biscuits and press gently until the filling almost reaches the edges.
- 19
Lightly dust the assembled alfajores with icing sugar before serving.
