Preheat your oven to 350°F (175°C). Lightly grease a donut pan with oil or non-stick spray.
Reduce the apple cider (optional but recommended): In a small saucepan, simmer the apple cider over medium heat until it reduces to about 3/4 cup (175 milliliters). This intensifies the apple flavor. Let it cool slightly before using. Measure exactly 3/4 cup for mixing in the next steps. If you evaporated it too much add apple cider.
In a large mixing bowl, whisk together flour, brown sugar, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and cardamon.
In another bowl, whisk the reduced apple cider, applesauce, melted vegan butter, and vanilla extract until smooth.
Pour the wet mixture into the dry ingredients and gently fold until just combined. Do not overmix; the batter should be slightly thick.
Spoon or pipe the batter into the prepared donut pan, filling each cavity about ¾ full.
Bake for 14-16 minutes, or until a toothpick inserted in the center comes out clean. Let the donuts cool in the pan for 5 minutes, then transfer to a wire rack.
In a small bowl, combine sugar and cinnamon. Brush each warm donut with melted vegan butter, then roll in the cinnamon sugar mixture until well coated.
Notes
Room temperature: Transfer the cooled apple cider donuts to an airtight container or bag and store at room temperature for 3 to 4 days.
Freezer: Freeze these donuts in a freezer bag or airtight container for up to 3 months. Thaw them at room temperature or in the microwave.