Make the vegan buttermilk: In a large measuring cup, stir together 1 cup soy milk (or another non dairy milk) and 1 tablespoon apple cider vinegar (lemon juice). Set aside to curdle - this is your vegan buttermilk.
Whisk together the dry ingredients (flour, baking powder, and salt) in a separate bowl.
Stir the vanilla and maple syrup into the vegan buttermilk. Then pour the wet ingredients into the dry ingredients and stir just until combined (there will be some lumps). Add an extra tablespoon of milk if the pancake batter is too thick.
Let the batter sit while you heat the skillet. Pro Tip: Don't stir the pancake batter after it sits (keep the bubbles for the fluffiest pancakes).
Warm a lightly greased non-stick skillet/griddle over medium heat. If oil-free, use a non-stick skillet and skip the oil.
For each pancake, scoop ¼ cup pancake batter into the preheated skillet (leave room for the pancakes to spread). Cook over medium-low until bubbles start to appear and the edges look dry/cooked (~2 minutes), flip and cook on other the side until golden brown ~2 minutes. Repeat for remaining batter.
Serve immediately with your favorite pancake toppings!