Preheat your oven to 350°F (175°C) and grease a small oven-safe ramekin or baking dish with the coconut oil.
Slice the whole grain bread into 1-inch cubes and set aside.
In a medium mixing bowl, whisk together the egg whites, ground cinnamon, vanilla extract, and sea salt until well combined and slightly frothy.
Place half of the bread cubes into the prepared baking dish, followed by half of the fresh blueberries.
Layer the remaining bread cubes and blueberries on top.
Slowly pour the egg white mixture over the bread, ensuring all pieces are submerged or coated. Let it sit for 5 minutes to allow the bread to soak up the liquid.
Bake for 25-30 minutes, or until the custard is set and the top is golden brown.
While the bake is in the oven, mix the Greek yogurt with a splash of water or stevia if desired to create a creamy consistency.
Remove the bake from the oven, top with the Greek yogurt and a drizzle of maple syrup before serving warm.