Pour warm milk, melted butter and sugar into a large bowl and mix together to dissolve the sugar.
Add the dried yeast if you are using and allow it dissolve and foam (takes a few minutes).
Now add the flour, salt and sourdough starter to the mixture and stir into a dry, shaggy dough.
Use your hands to bring the dough together and pick up all the dry bits of flour. If you feel the dough is super dry at this point, add a splash more milk.
Tip the dough out onto the counter and knead until it's soft and supple (this will take around 5 to 10 minutes and can be done in a stand mixer if you'd prefer, but is simple enough to do by hand).
Place the kneaded dough into a bowl and cover with plastic. Allow the dough to rise.If you're using commercial yeast with sourdough discard, this will only take 1 to 2 hours in a warm environment.If you are using just active sourdough starter, this could take anywhere from 4 to 8 hours. The dough doesn't have to double, just rise by at least 50% and be puffy. Once the dough has risen, divide the dough into equal pieces. As these are a rustic type snack, they don't need to be weighed, however if you want to you definitely can.
Shape the dough into rough balls and allow the dough to rest for around 10 to 15 minutes on the counter.
Heat your choice of oil in a large pot (I use rice bran oil or vegetable oil). You want the temperature of the oil to be around 170C.See notes below for information about size of pot and type of oil. While the oil is heating up, roll the balls into "elephant ear" shaped pieces.
Add the cinnamon, sugar and salt to a bowl to create the cinnamon sugar and have it close to the oil.
When the oil has reached temperature, gently place one or two pieces of dough in at a time (depending on the size of your pot). Allow them to cook for a few minutes, turning once or twice, until they are golden brown.
Carefully remove from the hot oil and dip into cinnamon sugar.
Serve while hot and crispy.