Dulce de Leche

Dulce de Leche (Argentine milk caramel spread)

The classic Argentine spread: milk and sugar slow-cooked for hours with a pinch of baking soda until deeply amber, silky and fudgy. Use it between alfajores, swirled into ice cream, or eaten with a spoon.

Prep

10 min

Cook

180 min

Total

190 min

Serves

Makes about 450 g (16 oz), roughly 1 jar

Difficulty

Medium

Recipe ingredients

• •1000 ml (4 cups) whole milk, must be whole-fat; low-fat will not caramelise properly
• •250 g (1¼ cups) granulated sugar
• •1 tsp baking soda (bicarbonate of soda), do not omit; it prevents the milk from curdling and gives the smooth texture
• •1 tsp pure vanilla extract, added at the very end, off the heat

Steps

1. 1 Combine the whole milk, sugar and baking soda in a heavy-based, tall saucepan. The pan must be at least three times the volume of the mixture, because it will bubble up significantly. Whisk until the sugar and baking soda are fully dissolved.
2. 2 Place over medium heat and bring to a gentle boil, stirring constantly with a wooden spoon or silicone spatula to stop the mixture from catching on the base. Stay at the stove while it heats. Hot milk and sugar cause serious scalding burns, so keep children and pets away and never leave a boiling sugar mixture unattended.
3. 3 Once it reaches a boil, reduce the heat to the lowest possible setting so the mixture just simmers. This is the key step: patience over heat gives the colour and flavour without scorching.
4. 4 Simmer for 2.5-3 hours, stirring every 10-15 minutes and more frequently during the last hour as it thickens. Use the spoon to scrape the bottom and sides each time. Set a timer for each stir so the pan is never forgotten, and use a long-handled spoon so your hand stays away from the steam. If you must step away for more than a few minutes, turn the heat off and resume when you return.
5. 5 The dulce de leche is ready when it has reduced to about a third of its original volume, coats the back of the spoon thickly, drops in a heavy ribbon, and reads 105-107 C (220-225 F) on a sugar thermometer. The colour should be a deep caramel brown, not pale. Do not let it go above 110 C (230 F), where it scorches and turns bitter.
6. 6 Off the heat, stir in the vanilla extract. The mixture will keep bubbling gently for a moment. Let it settle for a minute before moving the pan.
7. 7 Pour into a clean glass jar that has been warmed with hot water and then dried, so the thermal shock does not crack it. Leave to cool completely at room temperature, uncovered or with the lid off, to let steam escape. It will thicken further as it cools. Do not seal a hot jar.
8. 8 Refrigerate once fully cold; it will keep for up to 4 weeks in the fridge in a sealed jar. If a skin forms on top, simply stir it back in before using.