Step 1

Heat the oven to 350°F. Whisk together the dry ingredients in a stand mixer bowl, including the sugar.

Step 2

In a large bowl, lightly whip the egg whites to aerate, then add the milk, eggs, and vanilla.

Step 3

In a stand mixer fitted with the paddle attachment, blend together the dry ingredients with the oil, and half of the milk mixture. Blend until combined, about 2 minutes. Scrape the bowl. Add the remaining milk mixture in two more batches, scraping in between each and blending to combine, about 6 minutes, or until no lumps remain. Fold in the gingers.

Step 4

Lightly spray the bundt pans with cooking spray, then coat with a light dusting of flour. Evenly divide the batter between the pans and bake 30 to 45 minutes, or until a cake tester comes out clean.

Step 5

Let cool completely before icing. Top with more crystallized ginger.

Step 6

Sift the powdered sugar into the oat milk. Whisk together, adding the ginger and salt. Add a touch more milk to get desired consistency, if necessary.