Let's prepare the dough. In a dough mixer bowl dissolve the yeast in some lukewarm (25-30°C/77-86°F) plantbased milk for a few seconds at low speed.
Add the rest of the ingredients and work the dough on low speed for 5 minutes.
Increase the speed to high and work for other 10 minutes.
Shape the dough into a ball and prove for 2-3 hours at 20°C/68°F (the oven with the light on will also do the trick).
Transfer our dough in the fridge for at least another 2 hours.
Cut the dough into 6 parts, shape each piece of dough into a ball and, with a rolling pin, form 3mm thick discs (make sure to sprinkle some flour on the working surface and on the rolling pin).
Spread 18 g of margarine between each layer, stack the discs on top of each other as if they were pancakes, and seal the edges with your finger tips.
Roll the layered dough into a ½ cm thick disc, and start folding the dough to achieve even more layers. - First fold: both sides of the disc to the center. Refrigerate for 30 minutes. - Second fold: roll the dough into a rectangle, then fold the top and the bottom of it to the center. Refrigerate for 30 minutes. - Third fold: repeat second fold step one more time.
Roll the dough into a 1 cm thick rectangle. Trim the edged to have a neat shape, cut in half lengthwise, then each half into triangles.
Roll each triangle into croissants and arrange on a baking tray coated in baking paper. Refrigerate for at least 30 more minutes.
Transfer the tray with the croissant into the oven (turned off!) and prove for at least 3 hours (ideally overnight for freshly baked morning croissants).
Preheat the oven at 180°C fan assisted and bake the croissants for 15-20 minutes, until golden brown.
Sprinkle the croissants with vanilla flavoured icing sugar before serving. They're amazing warm or at room temperature!