Place the baking soda in a small bowl and line a baking sheet with parchment paper. Set aside.
In a 2 ½-quart heavy-bottomed saucepan, combine sugar, corn syrup and water. Heat over medium heat, stirring, until the sugar is dissolved.
Without stirring, bring syrup to a boil. Continue to cook without stirring, using a pastry brush dipped in water to wash down side of saucepan (this is to wash away stray sugar crystals and prevents the syrup from crystallizing), until caramel turns a very light golden color.
Remove caramel from the heat and whisk in the baking soda for 3 to 5 seconds; the caramel will start to bubble and swell. Pour bubbling caramel onto the lined baking sheet. Allow to cool, undisturbed, until room temperature.
Fill a saucepan with water and bring to a gentle simmer. Place chocolate in a medium heat-proof mixing bowl and set over saucepan, making sure the bowl doesn't touch the water. Cook, using a flexible spatula to stir occasionally, until chocolate has melted, 3 to 4 minutes.
Using a clean, dry pastry brush or the back of a spoon, spread melted chocolate over the honeycomb in an even layer. Sprinkle chopped salted peanuts all over. Let chocolate cool until set. Break candy in large chunks and serve.
