Check ingredients In a large bowl, using a whisk, mix together the cornstarch, nutritional yeast, orange zest, and ground cinnamon.
Whisk in the soy milk, ¼ cup of the maple syrup, and 2½ tablespoons of the Grand Marnier. One at a time, drop the slices of bread into the liquid mixture and let sit in the mixture for 10 seconds to soak it up slightly, then transfer to a baking dish (large enough to fit all the slices of bread in a single layer is preferable, but you can also stack them on top of eachother.
Pour any of the remaining liquid onto the soaked slices of bread and cover with foil. Refrigerate for at least 8 hours and up to 24.
When you’re ready to cook, heat the oven to 200ºF and line a sheet pan with parchment paper.
Lay out the bread in a single layer (if not already) and lightly dust some flour on the face-up sides of the slices (I used about ¼ teaspoon of flour per slice.) Melt about ½ teaspoon of vegan butter into a nonstick skillet over medium heat. Place 2 slices of soaked bread onto the pan, floured side-down, and cook until golden-brown, about 2 to 3 minutes.
Lightly dust more flour onto the now-face-up sides of the bread. If you find that the pan is getting so hot that the bread starts to scorch, drop the heat to medium-low. Flip the bread and cook for an additional 2 to 3 minutes, then place on the parchment-lined sheet pan, then transfer to the oven to keep warm.
Repeat with the remaining slices of bread, placing cooked pieces on the same sheet pan and returning to the oven as they are ready.
Before serving, prepare the Grand Marnier syrup. Mix together the remaining ¼ cup of maple syrup and ½ tablespoon of Grand Marnier. (The syrup can easily be doubled if desired.)
Serve the French toast warm, garnished with Grand Marnier syrup and dark chocolate shavings.
