In a medium bowl combine the first 4 ingredients (flour, salt, baking powder and cinnamon). Set aside. Beat the eggs and sugar in the bowl of an electric mixer fitted with the paddle attachment. Mix to combine and then beat on high for 5 minutes until light and fluffy. Add the cider and the melted butter to combine. Remove bowl from the electric mixer and gradually add the flour mixture by hand stirring to combine with a wooden spoon or sturdy rubber spatula. Cover dough and chill for at least 2 hours.

Roll dough out on a lightly floured surface. Dough should be about ½ inch thick. Using a standard donut cutter cut out donuts. Heat oil to 375 degrees. At this point you can either fry them as is or give them a little inside out twist taking one outside edge and bringing it in through the center hole (This will add a little more homemade look and feel and crunch to the outside of the donut). Either way, place 2-3 donuts in the oil at a time depending on the size of your pot of oil. Donuts should cook for 1-1 ½ minutes per side. Remove from oil and drain on paper towels or brown bags. When donuts are warm you can shake them in a bag with a cinnamon-sugar mixture (1/2 cup sugar, 1 tsp. cinnamon).