Heat the oven to 200°F or if your oven has a proof setting, turn it on.
In a medium size bowl, combine the melted butter, buttermilk, pineapple juice and brown sugar. Slightly whisk so that it's all combined. Wait a bit until mixture cools a bit (if it's too warm from the melted butter) then add the extracts.
Meanwhile, in the bowl of your mixer, combine 3¾ cups of flour, yeast, salt and ground ginger. Using the paddle attachment, turn the mixing speed on low and slowly pour in the wet ingredients. Continue mixing while adding the 2 eggs and egg yolk. A sticky dough will begin to form. Switch to the hook attachment and knead the dough for 7-8 minutes, adding ¼ cup more of flour if necessary. Do note that this is a very sticky dough, so don't add any more than 4 cups of flour total!
Once the dough has been kneaded, form into a ball and place in a large metal or glass bowl that has been lightly greased. Cover with a clean towel or plastic wrap, turn OFF your oven, place inside and allow to rise for about 1 to 1½ hours or until doubled in size. I use this trick all the time to speed up the rising time.
Once the dough has doubled, remove and gently deflate. Divide into 15 equal pieces. Roll into circles and place in a parchment lined 9x13 pan. Heat oven to 200°F. Generously butter the tops and sides of each roll. Place a clean kitchen towel over top. Turn OFF your oven and place the covered rolls inside to rise until doubled in size.
Remove the rolls from the oven and turn on your oven to 350°F.
Brush the rolls with egg. Once heated, bake the rolls for 22-25 minutes or until the tops are golden brown in color.
Remove the rolls from the oven. Another option is to skip brushing them with the egg wash and bake them, then brush them with melted butter once out of the oven.