Add the dry yeast to warm water along with half the sugar in a medium sized bowl and keep it aside.
Preheat the oven to 400 degrees and line the baking tray with a silicon mat and keep aside.
In a large bowl, mix together the flour, the rest of the sugar, baking powder, baking soda and salt.
Add the butter to the flour and start cutting it into the dough with a fork or pastry cutter. Once the butter is all mixed in, the flour should resemble the texture of sand.
Once the flour reaches the desired consistency, add in the yeast mixture and the buttermilk and mix the dough just until it stops sticking to the sides of the bowl.
Once the dough stops sticking to the sides of the bowl, transfer it to a clean, dusted surface and knead it lightly about 20-25 times.
Once you are done kneading the dough, roll it out until it is 1/2 inch thick.
Dust the round cutter with flour and start cutting out biscuits and placing them on the baking tray lined with a silicon mat.
Collect the scraps and roll the dough out again to cut out more biscuits.
Place the baking tray in the preheated oven and bake the biscuits for 12-15 minutes, until they have golden brown tops.
Once they are done, take them out of the oven and brush the tops with melted butter. Either serve hot or store for later!