In a small saucepan, over medium heat, start to melt butter and brown sugar. When butter is melted, add diced apples, lemon juice and cinnamon.
Lower temperature to medium-low, cover, and cook for about 15 minutes or until apples are soft. Stir occasionally.
Set aside all the juice from cooked apples and about 1/2 cup of apples for topping of cooked French Toast.
Whisk eggs, heavy cream, vanilla extract together, sugar and cinnamon together until smooth.
Slice French bread slices in the middle but not all the way through.
Preheat a cooking pan on medium heat and grease it with some oil.
Divide cooked apples evenly among four bread slices, stuffing them in the center cut. Lightly press the slices to close them and generously dip in egg mixture on both sides.
Cook French toast on medium heat for about 3-5 minutes on each side.
Top cooked French Toast with apples and syrup that you set aside.