Honeycomb candy
Line a 9 inch square pan with parchment paper (sides and bottom). Set aside until needed. For flatter honeycomb candy, line a half sheet baking pan with parchment paper or silpat.
Keep a spatula and a whisk ready, as you will need them towards the end of the cook time.
Place the sugar, golden syrup, water, and salt in a large saucepan (this mixture will expand a lot, so use a large pot with enough space). You can use honey if you do not have golden syrup. Or corn syrup if you have neither.
Gently stir to saturate the sugar with the water.
Heat over medium high heat, while swirling the pot frequently to ensure the sugar is dissolved.
Brush the sides of the pot with a pastry brush dipped in cold water to dissolve the sugar crystals on the side of the pot. Do NOT stir the sugar syrup.
When the sugar syrup comes to a boil and all the sugar has dissolved, clip a candy thermometer to the side of the pot.
Heat the sugar mixture until it reaches 300°F / 150°C. Swirl the pot as you heat the sugar to make sure the syrup is evenly heating (check several spots in the syrup with the candy thermometer to make sure it's evenly heating).
Get the prepared pan, whisk, and spatula ready when the is close to 300°F. You can an oven mitt for whisking the base in the following steps, if you like.