Preheat oven to 425. Line a muffin tin (I actually get about 15 standard-size muffins, so plan accordingly) with cupcake liners and set aside.

Zest the orange and set aside.

In a large bowl or the bowl of a stand mixer, beat the butter, oil, and sugars until smooth. Add the eggs and orange rind and beat until smooth. Add the baking soda, baking powder, salt, and vanilla (and orange extract, if using) and beat until smooth. Alternately add the flour and buttermilk, starting and ending with the flour, mixing completely after each addition.

Scoop the batter into the lined muffin tins (I used a 1/4 cup cookie/ice cream scoop and it worked perfectly).

Bake in the preheated oven for 15-17 minutes or until the muffins are golden on top. Remove from oven and cool completely on cooling racks.

When the muffins are cool, melt 1/4 cup butter in a small mixing bowl. Add the zest of another orange. Slowly whisk in 1 cup of powdered sugar 1/4 cup at a time, beating thoroughly to eliminate any lumps. When you've added 1 cup of powdered sugar, it should look like moist frosting. Whisk in a few tablespoons of buttermilk until a smooth glaze consistency is reached.

Grab each cooled muffin by the bottom and dip it into the glaze. Allow the glaze to set up before serving (or don't...we're talking about glazed donut-like things here...it's hard to go wrong).