Place softened ice cream in blender and whip. Add cinnamon to coffee, stir, and add to ice cream. Mix well in blender. Melt chocolate (or use chocolate syrup) and add to blender. Pour into coffee mugs. If mixture becomes too chilled from the ice cream, simply put mug of coffee in the microwave to heat up.
For the topping, beat cream, pinch of nutmeg, 1 tablespoon brown sugar, and 1/2 teaspoon vanilla in a bowl until stiff peaks form. Top warm coffee with cream and sprinkle with nutmeg, cinnamon, or chocolate sprinkles.