In the bowl of a stand mixer, add milk, water, and active dry yeast. Let sit for 5 minutes. 

In a separate bowl, combine the dry ingredients. 

Add the egg and softened butter to the yeast mixture, then add the dry ingredients and mix on low speed using the hook attachment.

Mix for 6 minutes, until dough is formed.

If necessary, knead by hand until smooth, then cover and proof until doubled in size, about 2 hours.

Butter a nonstick baking pan. After proofing, divide the dough into eighteen 55-gram pieces.

Form into balls and place in the nonstick pan a few centimetres apart. Cover with plastic wrap and proof until doubled in size once more, about 3 hours. 

When the dough is fully proofed, fire up your oven. Aim for 510°C on the stone baking board inside. (You can check the temperature quickly and easily using an infrared thermometer.) When the oven is up to temperature, brush the buns with melted butter, sprinkle with sea salt, and wrap in foil.

Place the pan in the oven and turn off the flames, allowing the residual heat to cook the buns for 10 minutes.

Remove the foil and turn the flame back on to get that classic golden brown colour on the top of the buns. Cook for 5 more minutes, turning occasionally to prevent any one side from getting too much colour. 

When the rolls are done, remove them from the oven, brush them with more melted butter, and enjoy.