First, make the cake. Preheat oven to 350F and spray two 6" round cake pans with nonstick baking spray. In a small bowl, whisk together the ground flaxseed with the water and set aside to thicken.
In the bowl of a stand mixer, combine the flour, baking powder, baking soda, salt, sugar, and cinnamon.
Add in the vegan butter, and beat on low until it's incorporated and has a sandy texture.
In a small bowl, whisk together the oil, flaxseed mixture, nondairy yogurt, and vanilla extract, and add them to the dry ingredients. Mix until combined.
Pour in the unsweetened nondairy milk, and beat on medium-low until smooth and creamy. Finally, gently stir in the peach pieces.
Divide batter evenly among the 2 pans, and bake for 45-55 minutes until cake is set in the center and a toothpick comes out clean.
When the cakes are completely cooled, you can make the frosting. In the bowl of a stand mixer, beat the shortening, vegan butter, vanilla extract, and cinnamon together until completely smooth and creamy. Add in the powdered sugar, 1 cup at a time, until a thick frosting forms. Add in the salt.
To assemble the cake, divide the 2 cake layers in half to create 4 thin layers.
Place one cake piece on your cake stand or platter, and spread some white frosting on top. Arrange the thinly sliced peaches on the cake, then spread a bit more frosting on top. Repeat with all.
Next, cover the cake with the remaining frosting. I always like the "naked" look, so I cover the cake and use a bench scraper to get rid of any excess. Repeat to fill any gaps!
Let the cake chill for 30 min-1 hr before covering with the ganache.
Either make the white chocolate according to directions, or place about ½ cup of candy melts/almond bark in a microwave-safe bowl. Add in a splash of nondairy milk, and microwave in 20 second intervals until smooth and creamy. Add more milk and keep stirring if the mixture is too thick.
Transfer your white chocolate ganache to a squeeze bottle, and decorate the cake. Finally, add some peach pieces or small peaches on top for decoration. You can also add on some flowers if you'd like!
Allow the cake to chill until it's time to serve, and store leftovers in the fridge. Enjoy!