A savory buttery flavor that bursts in your mouth! Best Coffee buns recipe

160g bread flour
50g water
45g milk
3g yeast
3g salt
20g sugar
10g unsalted butter

40g unsalted butter, a little salt
or
Salted Butter 40g (2g x 20ea)

20g unsalted butter
20g sugar
15g eggs
25g cake flour (if not available, all-purpose flour)
1 tsp instant coffee
1.5 tsp hot water