Mix cream cheese, brown sugar, 2 teaspoons of the cinnamon and 1 teaspoon of the vanilla in small bowl until well blended. Spread 2 tablespoons of cream cheese mixture on each of 8 slices of bread. Spread 1 tablespoon of preserves on each of the remaining 8 slices of bread. Press one each of the bread slices together to form 8 sandwiches.
Beat eggs with wire whisk in 13x9-inch baking dish. Stir in milk, remaining 1 teaspoon cinnamon and remaining 1/2 teaspoon vanilla until well blended. Dip sandwiches in egg mixture, soaking for 2 minutes on each side.
Melt 1 tablespoon of the butter in large nonstick skillet or griddle on medium-low heat. Place 4 of the sandwiches in skillet. Cook 4 to 5 minutes per side or until golden brown. Repeat with remaining sandwiches, melting remaining tablespoon butter in skillet. Serve French toast with maple syrup, if desired.