Make the vegan buttermilk. Mix together the plant based milk and lemon juice, and set aside to curdle for one minute.
1 cup plant based milk, 1 tbsp lemon juice
Mix together the flour, sugar, salt, and baking powder. Then, add the vegan butter/margarine, and mix together using a fork until a fine crumb forms.
½ tbsp sugar, 1 tsp salt, 1 tbsp baking powder, 2.8 oz vegan butter, 3 ¼ cups all-purpose flour
Add the buttermilk, and continue mixing using either a fork or a wooden spoon until a shaggy dough forms.
Preheat the oven to 350 degrees F/180 degrees C.
Transfer the dough to a lightly-floured surface and roll out into a rectangle around an inch in thickness. Then, fold in the upper and lower edge, and roll it out once again.
Use a cookie cutter to cut out circles around 3 inches in diameter and transfer them to a baking tray lined with parchment paper.
Brush with some melted vegan butter if desired, then bake in the preheated oven for 18-20 minutes, until lightly golden brown on top.