A tasty treat for breakfast! I prepared it in the evening, and then my Mom got up at 2AM to turn on the slow cooker so we could have it for breakfast. Yum!
Line a 3½ or 4 quart slow cooker with a disposable slow cooker liner (I sprayed mine with nonstick spray instead... and it turned out fine, but the edges were a little crispy). Place the bread cubes in the prepared slow cooker.
In a large bowl, whisk together the milk, sugar, eggs, vanilla, cinnamon and salt. Pour over the bread cubes in the slow cooker. Press the bread down lightly with the back of a large spoon to moisten the bread completely. Cover and chill in the refrigerator for 4 to 24 hours.
Cover and cook on low-heat setting for 7 to 8 hours or until a knife inserted in the center comes out clean. Turn off the slow cooker. Carefully lift the disposable liner from the slow cooker, and then use a plate to transfer the French toast to a cutting board. Slice the French toast or spoon into serving dishes. Top with maple syrup.