In a large, shallow bowl, whisk together the powdered sugar, cornstarch, and cinnamon. Add three eggs, 1/2 cup of milk, and the vanilla extract, whisking until the mixture is smooth and well combined.

Dip each slice of bread into the egg mixture, ensuring both sides are coated but not completely soaked. Place the slices in a large skillet over low-medium heat. Cook for 3 to 5 minutes per side until golden brown and crispy. Remove from the pan and set aside on a plate, covering them to keep warm.

In a separate prep bowl, whisk the remaining four eggs with 2 tablespoons of milk and a pinch of sea salt. Pour the mixture into a skillet over low heat. Use a spatula to gently swirl the eggs. When the eggs are nearly set, add dollops of mascarpone cheese and stir until melted. For a bit of texture, turn the heat up to high for the last 30 seconds to crisp the edges.

If you haven't already, cook your bacon until crispy. Using an air fryer at 400 degrees Fahrenheit for about 8 to 10 minutes is a great way to get perfectly crispy bacon with minimal cleanup.

Lay out your cooked French toast slices. Spread 1 tablespoon of cream cheese on one slice and 1 tablespoon of blackberry jam on another. Layer two slices of crispy bacon and a portion of the mascarpone scrambled eggs onto the jam-covered slice.

Press the cream cheese-covered slice on top to close the sandwich. Cut the sandwich in half diagonally. Top with a drizzle of maple syrup, a dusting of powdered sugar, and a few fresh blackberries. Serve immediately while warm.