Sprinkle the yeast on top and give it a gentle mix.
Cover the bowl and keep aside for 10-15 minutes.
The yeast should bloom and the mixture should be frothy. If not, either the milk mixture was too warm or the yeast was expired. Do not attempt to make the buns in either of the case.
Add flour, olive oil, salt and remaining sugar in a bowl and mix.
Add the yeast mixture in the flour and knead to make a smooth dough.
Take out the dough on a floured surface and knead it for 5-6 minutes.
If using a stand mixer, knead the dough for 3-4 minutes on medium speed.
Transfer the dough in an oiled pan and cover and keep aside for an hour until it doubles in size.
Divide the dough in 24 - 26 equal parts and roll each part in a tight round.
Line a baking sheet with parchment paper and arrange the dough balls on the sheet keeping distance of 1 inch between each ball.
Cover and keep aside for 30 minutes.
Preheat the oven to 180 degrees C.
Mix egg yolk and water in bowl and brush the buns with this mixture. You can also brush the buns with Milk if you don't like the smell of eggs.
Sprinkle sesame seeds and poppy seeds on top.
Bake for 15-20 minutes until golden brown.
Remove the tray from the oven and transfer the buns on a wire rack.