Heat the olive oil in a large sauté pan over medium-high heat, and add the sliced apples to the pan.
Mix the cinnamon and nutmeg with the apple cider and pour over the apples. Stir well to combine the apples with the cider/spice mixture.
Bring the mixture to a boil, and then reduce the heat to low, cover, and let apples simmer until they are softened and the liquid is thickened. Add 2 teaspoons of the syrup or sweetener and stir well to combine. Taste and add additional sweetener if desired.
While the apples are simmering, spray the bottom and sides of an 8-inch cake pan with nonstick spray and set aside.
Combine the eggs, milk, cinnamon, vanilla and remaining syrup or sweetener in a measuring cup and set aside.
Line the bottom of the pan with the cooked apples. Fit the slices of bread over the apples, trimming any pieces as needed so that all of the apples are covered.
Pour the egg mixture over the bread and gently press down with a spatula to make sure the egg soaks into all of the bread.
Cover the cake pan with plastic wrap, and weight it down a bit with a plate. Refrigerate overnight or until ready to bake.
To Make the Syrup:
Heat the cider, syrup, and vanilla in a large saucepan, and bring the mixture to a boil. Reduce the heat to medium, and let it reduce until you have approximately ½ cup. It will thicken a bit, but will not be the same consistency as syrup. Taste and adjust sweetener as desired.
To Bake:
Preheat the oven to 325 degrees. Remove the plastic wrap from the French toast, and bake for about 40-45 minutes or until the bread is puffed, and lightly browned and the eggs are cooked through.
Let cool for about 10 minutes, invert the pan onto a large serving plate, and cut into slices.
Notes
You can assemble the french toast the night before and bake it in the morning when guests arrive.