Line a baking sheet with parchment paper and set it beside the stove for quick access.
In a medium saucepan over medium heat, stir together sugar, corn syrup, water, and salt until the sugar fully dissolves.
Stop stirring and attach a candy thermometer. Let it boil undisturbed for 5–7 minutes, until it reaches 300°F (150°C).
Remove from heat and quickly stir in butter, vanilla, and baking soda. Add food coloring now if using and mix well—the mixture will foam.
Pour onto the prepared baking sheet. Let it spread on its own or use a spatula to even it out.
After 5 minutes, when the surface is tacky but not sticky, sprinkle with edible glitter or sprinkles.
Let it cool completely for about 30 minutes. Once set, break into pieces by hand or use the back of a spoon.