Preheat the oven to 220C/425F. Line a large baking tray with parchment paper and set aside.
In a small bowl, add the almond milk with apple cider vinegar and let it sit for several minutes to curdle. This will be a mock buttermilk.
In a large mixing bowl, add your flour, baking powder, sugar, and salt. Add your chopped butter, and use your hands to mix into the dough until a crumbly, thick texture remains. Add your milk mixture and mix until just combined.
Lightly flour a kitchen surface. Transfer your dough onto it. Roll out the dough until it is an inch in thickness. Then, use a biscuit or scone cutter to cut the biscuits out and place them on the baking tray. If desired, brush some extra milk on top.
Bake the biscuits for 12-15 minutes, or until golden brown on top. Remove from the oven and transfer to a cooling rack for several minutes.
Notes
* You can substitute for margarine. Butter/margarine must be firm. TO STORE: Leftover biscuits can be stored at room temperature in a sealable container, for up to 5 days. They can also be stored in the refrigerator, for up to 14 days (2 weeks). TO FREEZE: Freeze leftover biscuits in a ziplock bag, and keep in the freezer for up to 6 months. TO THAW: Biscuits must be thawed to room temperature, before reheating. It is best to thaw overnight in the fridge.TO REHEAT: Heat in the microwave for 20-30 seconds, or in a preheated oven for 10 minutes (at 180C/350F).