01 - In a small mixing bowl, beat the softened cream cheese, granulated sugar, and vanilla extract together until completely smooth and creamy. Gently fold in the fresh blueberries, taking care not to crush them.
02 - Lay out 4 slices of brioche on a clean work surface. Divide the cheesecake filling evenly among them, spreading a generous layer to near the edges. Place the remaining 4 slices on top to form 4 stuffed sandwiches, pressing gently to seal.
03 - In a wide shallow dish, whisk together the eggs, whole milk, ground cinnamon, and salt until fully combined and uniform in color.
04 - Carefully dip each stuffed sandwich into the egg custard, allowing each side to soak for 10 to 15 seconds. Ensure both sides are evenly coated but not oversaturated, which could cause the filling to seep out.
05 - Melt the butter in a large nonstick skillet or griddle set over medium heat. Once the butter begins to foam, place the soaked sandwiches in the pan and cook for 3 to 4 minutes per side until deeply golden brown and cooked through. Work in batches if necessary to avoid crowding the pan.
06 - Transfer the cooked French toast to serving plates. Dust generously with powdered sugar and finish with additional fresh blueberries, a drizzle of warm maple syrup, or a dollop of whipped cream as desired. Serve immediately while hot.