Using a paring knife, cut through the bottom crust of each slice of bread horizontally, to create a pocket that your fruit filling can be stuffed into.
In a small mixing bowl, combine the softened cream cheese, Strawberry Jam and lemon zest. Fold in the blueberries. Place the mixture into a re-sealable bag. When you are ready to stuff the bread you will snip off a corner of the bag and pipe the filling in.
In a baking dish, whisk together the milk, 1 tablespoon melted butter, brown sugar, vanilla, cinnamon and eggs.
In a large, heavy-bottomed skillet melt the 2 tablespoons butter over medium heat.
Using the re-sealable bag as a pastry bag, stuff each slice of bread with about 2 tablespoons of the cream cheese mixture. Once the slices are stuffed, place each slice into the milk and egg mixture for about 10 seconds per side. Once the slices are coated with the custard base, place them into the skillet to brown. Work in batches. Cook each slice of stuffed French toast until golden brown, 4 to 5 minutes per side. If cooking a large batch, transfer the cooked French toast to a baking sheet and keep warm in a 200 degree F oven while you cook the rest of the slices. Repeat the process with the remaining French toast. Serve warm, topped with extra berries, powdered sugar and maple syrup.
In a saucepan over medium-high heat, bring the strawberries, sugar and lemon juice to a boil. Reduce the heat to a simmer and stir often until the fruit thickens and becomes syrupy, 5 to 10 minutes.
Fill a large bowl with ice and a little water. Have a smaller mixing bowl that can sit within the larger bowl of ice. Once the fruit has cooked, add it to the smaller bowl and set it in the ice bath to cool. As the fruit cools it should become gel-like. Once the jam has cooled it can be stored.