Line a large baking sheet with a silicone mat or parchment paper.
Sprinkle the yeast into the water and leave for 5 to 10 minutes until it starts to look frothy, then stir to dissolve.
In a large bowl combine the flour, butter, sugar, 1 egg, and salt.
Add the yeast water and combine all ingredients with a rubber spatula.
Turn the dough out onto a floured surface and knead for 5 - 10 minutes until the dough is soft and smooth.
Grease a large bowl with the olive oil and place the dough in the bowl. Turn the dough over once so that it picks up a bit of oil on both sides.
Cover the bowl with a kitchen towel and let the dough rise for about 1 to 1 1/2 hours.
Once the dough has doubled in size, turn the dough out on a floured surface and divide the dough into 8 pieces.
Shape each piece into a flat disc about 1/2 inch thick and place each on the prepared baking sheet.
Drape a piece of plastic wrap over the baking sheet. Do not seal tightly.
Let the buns rise another 45 minutes to 1 hour until they have doubled in size.
Preheat the oven to 375°F.
Beat the remaining egg with the milk.
Lightly brush the tops of the buns with the egg wash without deflating the dough.
Sprinkle each bun with sesame seeds.
Bake for 15 - 17 minutes or until golden brown.
Let cool completely, slice, serve and Enjoy!