Preheat the oven to 350°F (180°C). Generously grease a 12-cup Bundt pan, making sure to coat every crevice, then dust it lightly with flour and tap out the excess.

In a medium bowl, whisk together the flour, salt, baking powder, and baking soda. Set aside.

In a large mixing bowl, beat the butter for about 2 minutes, until smooth and creamy. Add the sugar and the vanilla bean seeds, if using, and continue beating for about 3 minutes.

Add the oil and keep beating until the mixture becomes pale, light, and fluffy.

Add the eggs one at a time, mixing well after each addition and scraping down the sides of the bowl as needed. Along with the final egg, add the vanilla bean extract or vanilla bean paste.

Mix in the sour cream. Add half of the dry ingredients and mix on low speed just until combined. Pour in the milk and mix until incorporated. Add the remaining dry ingredients and mix only until no dry streaks remain, being careful not to overmix.

Transfer the batter to the prepared Bundt pan and smooth the top with a spatula. Bake for 45 to 60 minutes, or until the cake is golden and a toothpick inserted into the center comes out clean or with a few moist crumbs attached.

While the cake is baking, prepare the vanilla bean syrup. Combine the sugar, water, and vanilla bean seeds, if using, in a small saucepan over medium heat.

Bring the mixture to a gentle simmer, stirring occasionally, just until the sugar has completely dissolved. Remove from the heat and keep warm.

If using vanilla extract instead of the seeds, simply add the extract after you remove the syrup from the heat.

Once the cake is out of the oven, let it cool in the pan for 5 minutes. Using a skewer or toothpick, poke holes all over the exposed surface of the cake. Slowly spoon or brush the warm syrup over the cake, allowing it to soak in gradually. Let the cake cool in the pan for another 15 minutes before carefully inverting it onto a wire rack. Allow the cake to cool completely before glazing.

To make the white chocolate vanilla bean ganache, place the chopped white chocolate in a heatproof bowl. In a small saucepan, heat the heavy cream with the vanilla bean seeds (or paste) until steaming but not boiling. Pour the hot cream over the white chocolate and let it sit undisturbed for 1 minute. Whisk gently until smooth, glossy, and fully emulsified.

Allow the ganache to sit at room temperature for about 60 minutes, stirring occasionally, until it thickens to a pourable consistency. Once the cake is completely cool, pour the ganache over the top, letting it drip naturally down the sides before serving.

If the ganache is too runny, you can place it in the fridge for about 5 minutes. Stir gently. Then let it rest on the counter for 10 minutes before pouring over the cake.

Decorate with the white chocolate curls, if making them.