Step 1

Preheat oven to 425 degrees. Spray 12 cavities of donut pans with non-stick cooking spray, set aside.

Step 2

In a medium mixing bowl whisk together flour, baking powder, baking soda, salt and nutmeg, set aside.

Step 3

In a seperate large mixing bowl whisk together 4 Tbsp butter, the vegetable oil and sugar. Mix in eggs and vanilla extract.

Step 4

Whisk in 1/3 of the flour mixture, blending just to combined, mix in 1/2 the buttermilk just to combined, followed by 1/3 of the flour mixture, 1/2 the buttermilk, then last 1/3 of the flour mixture. Batter should be slightly lumpy, don't over-mix.

Step 5

Pour mixture into a piping bag (fitted with a large round tip if preferred). Pipe into donut cavities filling about 1/4-inch to the top.

Step 6

Bake in preheated oven until toothpick inserted into center comes out clean, about 7 - 8 minutes.

Step 7

Let cool in pan for a few minutes then invert onto wire racks to cool.

Step 8

For the glaze, in a small mixing bowl whisk together powdered sugar, butter, milk and vanilla. Thin with more milk as needed to reach a nicely spreadable consistency.

Step 9

Spoon and spread mixture over donuts, decorate with sprinkles right away if using. Let glaze set at room temperature.

Step 10

Donuts are best served the day the are prepared.