In a bowl, mix together the flour, cocoa powder, sugar, yeast, salt and baking powder.
In another small bowl, mix the warm milk with the oil and food coloring until combined. Add the wet to the dry ingredients and mix everything until dough comes together. Add more flour if it's too sticky or more milk or water if dough is not coming together.
Knead the dough for about 5 mins until smooth. Cover and let it rest for 1 hour.
After 1 hour, dough should have doubled in size. Divide it to 2, work with 1 half and keep the second half covered. Roll it into a rectangle, spread your chocolate filling leaving 1 cm on each edge without filling. Roll the dough from 1 side to the center and from the other side to the center so you have 2 logs attached in the center. Divide to 16 and pinch every part on the bottom so you have a heart shape.
Put in a pan, cover and let the hearts rise again for 45 mins.
After 30 mins, hearts should be puffed up. Preheat your oven to 200°C and bake the hearts for 20-22 mins until more puffed up. Enjoy warm!