Preheat oven to 375 degrees F and line a large baking sheet with parchment.
In a large bowl, stir together the peanut butter, maple syrup, ¼ cup coconut sugar, and vanilla.
Add the flour, baking soda, and salt (if using), and stir until fully combined. Use a cookie scoop or a tablespoon to scoop 1.5 Tbsp dough into your hand. Roll the dough betwen your palms to smooth it out, and place on cookie sheet 2 to 3 inches apart.
Place the 2 tsp sugar in a small bowl. Use the underside of a fork to create a criss-cross pattern on top of one ball of dough, gently pressing down to flatten it into a cookie shape. Now dip the underside of the fork tines in coconut sugar (this will help it not stick to the dough). Repeat with the remaining cookies.
Bake 10 to 12 minutes. The cookies will be very soft when removed from the oven. Allow cookies to cool on the baking sheet for 5 minutes, then transfer to a rack to cool completely.
StorageStore cookies in a container at room temperature or refrigerated for up to 5 days. Cookies can also be frozen. Be sure they're well-protected from air.Unbaked cookie dough can be frozen, as well. Place rolled cookie dough balls on a baking sheet and freeze for about 30 minutes. Then transfer to an airtight container and freeze until ready to bake. Bake from frozen, adding 1 to 2 minutes to the bake time.