In the bowl of a stand mixer, whisk together flour, sugar, yeast and salt.(If using active dry yeast, please combine with 2 tbsp lukewarm water +1 tsp sugar and set aside to activate for 10 min).
Add plant milk, and knead on slow to combine.
Add the softened butter, diced, then continue kneading until well incorporated (about 10 mins). The dough must be smooth and slightly sticky.
If the dough is a little bit warm, let cool for a few minutes at room temperature, then add the chocolate chips and spread evenly in the dough.
Cover the dough with a cloth and let rise at room temperature for 1 hour or until doubled in size.
After the first rise, punch it a little bit to remove any air bubbles.
Place the dough back in the bowl, cover with cling film, and place in the refrigerator for about 3 hours or ideally overnight.
Divide the dough into 16 equal pieces (65g each) and shape into small balls. Do not overwork or the chocolate will melt.
Brush with some plant milk, cover, and let rise for 1 hour.
Preheat the oven to 175°C (350°F).
Brush the buns with plant milk again. Bake for about 15-17 minutes, or until the buns are golden-brown. Transfer to a rack and let cool completely. Enjoy!