Prepare a campfire with hot coals and low flames.
Grease a large piece of aluminum foil with butter or cooking spray and shape it into a boat. Place bread loaf inside, standing up to keep its loaf shape. (Add another piece of foil underneath for extra support.)
In a large liquid measuring cup, whisk together eggs, milk, sugar, vanilla, and salt. Carefully pour over bread, making sure to get between each slice.
Wrap entire loaf in foil. Place over campfire, directly on hot coals but not over the flame. Cook until egg mixture is cooked through and bread is lightly toasted, about 40 minutes. Rotate loaf occasionally to ensure even cooking on all sides. (Alternately, you can bake in a 375° oven for about 40 minutes.)
Let sit for 10 minutes before serving. Unwrap loaf; dust with powdered sugar and garnish with sliced strawberries. Serve warm with syrup.