Place a silicone mat or parchment paper onto a baking sheet and set aside.
Add the coconut sugar, maple syrup, and water to a heavy bottomed nonstick pot. Make sure you have at least 6 inches above the sugar mixture. When the sugar boils, it can easily boil over if the pot is not large enough. Using medium heat, bring the mixture to a simmer. Watch it carefully, so that it doesn't boil over.
Once it has simmered, add in the peanuts and stir. Attach your candy thermometer to the side of the pot. Continue to simmer over medium-low until the mixture reaches 300 degrees, or the "hard crack" stage in candy making terms. This can take up to 30 minutes or more, so don't worry if it seems like your sugar temperature will never get there, it will.
Once the temperature reaches 300 degrees, immediately remove it from the heat. Add in the peanut butter and baking soda and whisk thoroughly to combine. The mixture will lighten up and become one color once everything is mixed through. Working quickly, pour the mixture out onto your baking sheet with a silicone mat and use a spatula to spread it out into an even layer. Let it sit on the baking sheet until hardened. You will know your brittle is done when it is stiff and snaps into pieces easily. Serve.