In the bowl of a stand mixer fitted with the paddle attachment, cream butter and granulated sugar until light and fluffy, about 2 minutes. Add eggs, one at a time, beating well after each addition.
1 cup unsalted butter, 2 cups granulated sugar, 5 large eggs
With the mixer on low, alternate adding the buttermilk mixture and flour mixture to the bowl, beginning and ending with the flour mixture.
Pour batter into prepared bundt pan and bake for 50-60 minutes, or until toothpick inserted into cake comes out clean. If the top is browning too quickly, you can tent it with a piece of foil.
Cool cake completely before flipping it out onto a cooling rack. Let cool for another 30 minutes after you've flipped it out on a cooling rack.
In the meantime, make the orange glaze by whisking together orange zest, powdered sugar, and orange juice. Add more orange juice if you like a looser glaze.
Zest of 2 oranges, 2 cups powdered sugar, 2 tablespoon fresh orange juice
Pour glaze over top of the bundt cake. Cut and serve.
Store in an airtight container for up to 5 days.
Notes
This can be made in 2 loaf pans if you don't want to make this in a bundt pan. Ingredients, directions, and cook times are all the same.