In a mixing bowl, whisk together plant-based milk, vinegar, syrup, vanilla, and melted butter. Set aside.
In another large mixing bowl, stir together all the dry ingredients, buckwheat flour, baking soda, baking powder, salt, and cinnamon. Make a well in the center and pour the liquid ingredients into the well.
Whisk the batter until it becomes slightly smooth with little to no lumps. Once whisked, let the batter sit to rest for 5 to 10 minutes.
Warm your waffle iron to medium heat and spray with a little coconut or avocado oil.
Pour ½ cup of batter, or more depending on how large your waffle iron is, onto the warm oiled waffle iron and cook for 3 to 4 minutes or until the waffle exterior is crispy and golden brown.
Serve immediately or cool on a rack while you are cooking the rest of the batter. You should be able to make around 6 waffles.
Serve with toppings of your choice like maple syrup, nut butter, plant-based yogurt, berries, banana slices, coconut whipped cream, whatever your heart desires!
Store the cooked waffles for up to 2 days in an airtight container in the fridge or freeze in an airtight container for up to 3 months. You can rewarm the waffles in a toaster.