Prepare the keto sourdough baguettes by following this recipe (you can make 8 regular or 16 mini baguettes).
Prepare the garlic butter (or any other flavoured butter).
Make sure all the ingredients have reached room temperature before mixing them in a medium bowl.
Cut the baked baguettes in half and spread the flavoured butter on top of each half (1-2 teaspoons per piece).
Sprinkle with grated Parmesan and place back in the oven to crisp up for a few more minutes.
When done, remove from the oven.
Optionally, drizzle with some olive oil and serve while still warm.