Bring pumpkin puree, pumpkin pie spice, and ginger to a sputtery simmer in a medium saucepan. Reduce heat to medium-low and cook, stirring frequently, until mixture starts to stick to the pan bottom, 5 to 7 minutes; cool to room temperature.
Adjust oven rack to lower-middle position and heat oven to 375 degrees. Mix flour, baking powder, baking soda and salt in a large bowl. Mix butter (or coconut oil), brown sugar, eggs, and yogurt in a medium bowl; Stir in pumpkin puree. Stir wet ingredients into dry ingredients. Scoop mixture into mini muffin tins and bake until set and browned, 15 to 17 minutes. Let cool a couple of minutes then remove from pan and set on a wire rack.
Mix sugar and cinnamon. Working one at a time, dip muffin top in butter (or coconut oil) then dredge in cinnamon sugar. Serve warm or at room temperature.
Recipe by Three Many Cooks at https://threemanycooks.com/recipes/sweet-treats/mini-pumpkin-doughnut-muffins/