Add maple syrup, vinegar, and water to a small sauce pan over medium heat.

Let the mixture come to a boil.

Add garlic and red pepper flakes.

Simmer the mixture for a couple minutes.

Add a splash of water to the arrowroot starch in a small bowl and stir to dissolve.

Add that mixture to the chili sauce and stir until thickened. This will be pretty quick.

Add the sauce to a jar with a lid.

Store in the fridge for up to one week.