Using an electric mixer, cream together the butter, oil and sugars. Beat in eggs one at a time, mixing well after each addition. Add vanilla.
In another bowl combine the remaining dry ingredients. Alternate adding a third of the flour mixture into the wet ingredients, followed by a third of the milk. Continue mixing on low until all is incorporated.
Spoon mixture into a large Ziploc bag and seal. Snip corner off and gently squeeze (half full) into the wells of a well greased mini doughnut pan. Bake at 425°F for 7-10 minutes until lightly golden brown (taste one to be sure inside is done).
Let cool in pan for 3 minutes, then carefully turn out onto wire rack.
While warm gently shake a few doughnuts at a time in a plastic bag filled with the sugared toppings of your choice. For chocolate glazed topping, allow doughnuts to cool completely before dipping.
Notes
Add 2 Tbsp cocoa for chocolate doughnuts Makes 48 mini doughnuts