Prepare the egg mixture: In a shallow bowl, whisk together the eggs, half-and-half, vanilla extract, cinnamon, nutmeg, and brown sugar until well combined. Set aside.
Make the strawberry filling: In a small bowl, combine the sliced strawberries, granulated sugar, and lemon juice. Let sit for several minutes to release the natural juices and enhance flavor.
Mix the cream cheese filling: In a medium bowl, beat the softened cream cheese, powdered sugar, and lemon zest until smooth and fluffy.
Assemble the sandwiches: Spread about 1½ tablespoons of the cream cheese mixture onto one side of a slice of bread, keeping the edges clean. Pat strawberries dry and layer them evenly over the cream cheese. Top with a second slice of bread to form a sandwich. Repeat with remaining bread.
Cook the French toast: Heat 2 tablespoons of butter in a skillet over medium heat. Dip each sandwich into the egg mixture, coating both sides thoroughly but not soaking too long. Cook for 2–3 minutes per side, or until golden brown and crisp. Add more butter to the skillet as needed.
Serve: Remove from the skillet and serve warm. Dust with powdered sugar and top with maple syrup, whipped cream, and fresh strawberries if desired.