Heat apple cider in a small saucepan over high heat. Bring to a boil; reduce heat and simmer, stirring occasionally, until reduced to 1 cup, about 15-20 minutes.  Let cool completely.  In a small bowl, combine granulated sugar and 1 tablespoon cinnamon; set aside.  In a large bowl, combine flour, brown sugar, baking powder, salt, baking soda, nutmeg, and remaining 1 1/2 teaspoons cinnamon.  In a large glass measuring cup or another bowl, whisk together butter, eggs, and apple cider.  Pour mixture over dry ingredients and stir using a rubber spatula just until moist;cover and place into the refrigerator until chilled, about 1 hour.  Divide dough in half.  Working on a lightly floured surface, roll dough into 1/2-inch thick rounds; cut out rounds with a 2 1/2-inch cutter.  Heat vegetable oil in a large stockpot or Dutch oven over medium high heat until a deep-fry thermometer registers 375 degrees Fahrenheit.  Working in batches, add donuts to the stockpot/Dutch oven and cook until evenly golden and crispy, 1 minute per side.  Transfer to a paper towel-lined plate for 30 seconds; then roll warm donuts in cinnamon sugar mixture to coat.  Serve warm.