Preheat the oven to 325°F. Generously butter a 10-inch Bundt pan, making sure to get into all of the curves and crevices. Lightly dust the inside with flour and tap out any excess.

Add the softened homemade butter, organic cane sugar, eggs, vanilla, flour, salt, baking powder, baking soda, and buttermilk to the bowl of a stand mixer fitted with the paddle attachment. Mix on low for about 30 seconds, just until the ingredients begin to come together. Increase to medium speed and beat for about 3 minutes, until the batter is smooth and well combined.

Spoon the batter evenly into the prepared Bundt pan and smooth the top. Bake for 65–75 minutes, or until a toothpick inserted into the thickest part of the cake comes out clean or with just a few moist crumbs.

As soon as the cake comes out of the oven, add the homemade butter, organic cane sugar, water, and vanilla to a small saucepan. Warm over medium-low heat, stirring frequently, until the butter has completely melted and the sugar has dissolved. Keep the heat gentle—the glaze should become smooth and glossy but should not boil.

While the cake is still warm and in the Bundt pan, use a thin knife or skewer to poke holes all over the cake. Slowly pour the warm butter glaze over the top, allowing it to work its way into the holes and soak through the cake.

Leave the glazed cake in the pan until it has cooled completely. Once cool, carefully invert it onto a cake plate or serving platter.

You can serve the cake once cooled, but it is especially good made a day ahead. Resting overnight allows the vanilla butter glaze to soak deeper into the crumb, making the cake even more moist and flavorful.