Step 1

Begin by preparing your tin. Line an 8x8 inch (20x20 cm) square tin with parchment paper, or grease it with butter, and set it aside.

Step 2

In a large heavy-duty saucepan, combine the brown sugar, condensed milk, milk, and butter. Place over medium-low heat, and using a rubber (heatproof) spatula, stir the ingredients till everything is combined, and the sugar has dissolved, and clip on your candy thermometer.

Step 3

Over low heat, bring the mixture to a rolling boil (this will take 5-10 min), stirring slowly but constantly. Be careful, the mixture is very, very hot! Let the mixture boil for around 13-15 minutes, stirring slowly but continuously, or until the thermometer reaches (240.8°F) 116°C. Be careful, the mixture is very, very hot!

Step 4

This is slightly at the high end of the soft-ball stage (which goes from 235°F to 240°F (113-116°C), but I find it works best for a firm fudge. For a softer, creamier variety, stop between 237°F (114°C) and 115°C (239°F). Keep an eye on the fudge, it will stay at 104°C (220°F) and then rapidly increase after that.

Step 5

Along with the candy thermometer, I also do a soft ball test, by dropping a little bit of the mixture into a glass full of icy water. Remove with your fingertips, and if it forms a soft, malleable ball that doesn’t stick to your fingers, you can off the heat. Stir in the vanilla and salt.

Step 6

Let the fudge cool to about 43-45°C (110°F), then beat the fudge for 10-15 minutes by hand (using a whisk or wooden spoon), or for several minutes (around with an electric mixer or until the mixture thickens significantly (it should look like soft cookie dough), and it’s lost its gloss and sheen (it should be matte). The longer you beat the fudge, the firmer the fudge will be. You’ll have to try this and see what you like.

Step 7

Working quickly, spread the fudge into your prepared tin, as best you can. Score the fudge using a knife, then let the fudge cool. If it’s still too soft, cool for longer. In this case, I prefer overnight (because it sets better the longer you wait).

Step 8

Then cut into squares. This keeps for up to two weeks and makes great gifts.