To make the dough, place the plant milk in a small saucepan and heat until lukewarm.
Remove from heat and crumble fresh yeast into the milk. If using active dry, sprinkle it over the milk and stir.
Place flour, sugar, and salt in a large bowl and pour milk mixture over the flour. Let sit for 10 minutes until the milk mixture looks bubbly.
Place margarine in the saucepan you used for the milk and gently heat until melted.
Remove from heat and pour over the plant milk mixture.
Knead the dough until combined, for about 1 minute.
Place a damp kitchen towel over the bowl and let the dough rest for 10 minutes.
Knead again until the dough is bouncy and smooth. This should take about 1-2 minutes.
Cover the dough again and let the dough rest at room temperature (20°C) for about two hours, or until approximately doubled in size.
Take the dough out of the bowl, punch it down, knead it briefly and shape into a ball.
Place on a lightly floured surface and roll into a rectangle. (Approx. 50 x 35 cm)
Cut cold margarine into very thin strips and place on top of the dough.
Mix sugar and cinnamon and sprinkle over the dough.
Also sprinkle dark chocolate on top.
Tightly roll the dough up, starting with the 50 cm side. Place on surface seam side down making sure to seal the edges of the dough.
Cut into 12 pieces. Use a chopstick or the handle of a wooden spoon to press a deep dent into the middle of the rolls.
Place on two baking sheets lined with parchment paper and cover with kitchen towels. Let rise for 30 minutes.
Place a deep dish baking sheet on the bottom of your oven and preheat to 250°C.
Right before you place the first sheet with buns in the oven, boil about a cup of water and carefully pour it into the baking dish.
Place one baking sheet at a time in the oven and immediately reduce temperature to 200°C.
Bake for 20 minutes or until golden brown.
After about 10 minutes the margarine should have melted and oozed out of the rolls. Open the oven door and brush the tops with the melted margarine. Then resume baking.
Repeat with the remaining rolls.
Let cool to room temperature before serving.