Mix the yeast and sugar to 42-degree water. Let it rest for about 10 minutes.
Add salt. Mix in most of the flours and add butter. Add the rest of the flours (note that 10 might be enough). Knead the dough even.
Line a deep baking tray with baking paper. Make rolls out of the dough and place them into the tray fairly close to each other. As they rise they should touch.
Let them rise for 30 minutes.
Spread melted butter on top and bake in 225-degrees for 20-25 minutes. Note that they might take a little longer to bake since they are so close to each others!