Place all 3 ingredient in a small bowl and whisk until smooth; set aside.
Make The Buttermilk Pound Cake:
Preheat oven to 325ºF (163ºC) Adjust an oven rack to the middle position.
In a medium mixing bowl, whisk together the flour (3 cups), baking soda (1/2 teaspoon), and salt (1/2 teaspoon); set aside.
In the bowl of a stand-up mixer, beat butter (1 cup) on medium speed, until light and fluff, 6 minutes. Gradually mix in sugar (3 cups) until blended. Beat on medium for 1 additional minute.
Add eggs (6), one at a time, mixing after each addition just until the yolk disappears.
Reduce mixer speed to low. Add flour mixture and buttermilk (1 cup), beginning and ending with flour mixture, on low speed until just combined. Scrape down the bowl as needed. Mix in lemon (1/2 teaspoon) and vanilla extracts (3 teaspoons).
Using a silicone pastry brush apply "homemade cake release" to every nook and cranny of a 12-inch nonstick bundt pan. Pour batter into the prepared bundt pan. Tap the pan on the counter to remove any air bubbles.
Bake for 45 minutes in the preheated oven. Cover with foil and continue to bake, about 32-35 minutes longer, or until a wooden skewer inserted into the center comes out with just a few moist crumbs, NOT completely clean. Cool in the pan on a wire rack for 10 minutes. Remove from the pan and cool completely on a wire rack.
Make The Glaze:
Meanwhile, make the glaze: add powdered sugar (1 1/2 cups) to a medium bowl. Add milk or cream to powdered sugar, 1 tablespoon at a time as needed, mixing well after each addition, until you reach the desired, thick but pourable consistency. Pour over completely cooled cake. Let the cake sit for the glaze to set, then serve.
Notes
Checking For Doneness: I like to pull my pound cakes out of the oven a little earlier than most cakes. I test for doneness with a wooden skewer and like it to have just a few moist crumbs on it.
Sticking: This cake can stick to the pan. I make a lot of pound cakes and I have always had great, if not perfect, results using Baker’s non-stick spray. That stuff is magical. For reasons I can't explain, it has not worked when I use it for this one pound cake. Weird, right?!
So I make a "homemade cake release," aka, Cake Goop, and apply it very generously to a nonstick 12-cup bundt pan with a silicone pastry brush. I'm very careful to get it into all the intricate details of the pan. It literally takes only a couple of minutes to make! The recipe is at the top of our recipe card.
Remember, if you happen to have any flaws, the glaze will help cover them up.
Make My Glaze Lemon: For an added lemony taste, you can use lemon juice instead of milk.