Preheat the oven to 180°C/160℃ fan/350°F/gas mark 4 and line a couple of metal baking sheets with baking paper.
Place the vegan butter, brown sugar and caster sugar in a bowl and whisk with an electric mixer until fluffy. Whisk in the vanilla bean paste and milk.
55 g (¼ cup) vegan butter/margarine (The solid block kind NOT spreadable - I use Stork block or Naturli Vegan Block), 75 g (⅓ cup + 1 rounded Tablespoon) light brown soft sugar, 30 g (2 rounded Tablespoons) caster sugar, ½ teaspoon vanilla bean paste/extract, 1 Tablespoon non-dairy milk
Sift together the flour, baking powder and cornflour and add to the bowl. Mix in until well combined then add the chocolate and stir through. The dough should be fairly stiff.
100 g (¾ cup + 1 Tablespoon) plain (all-purpose) flour, ½ teaspoon baking powder, 5 g (½ Tablespoon) cornflour (cornstarch), 80 g (3 oz) dairy free dark chocolate
Divide the dough into eight portions and roll each into a ball. Place them well spaced apart on the baking trays and flatten very slightly.
Bake for 10-15 minutes until pale golden, be careful not to overbake them, they will firm up as they cool. If they haven't spread much during baking, give the tray a hard tap on the countertop.
Leave to cool on the tray for 10 minutes then transfer to a wire rack to continue cooling. Enjoy straight away or store in an airtight container once cool.