You can use any type of bread- crusty french bread is great but I also use sandwich bread with great results- it will just be a little softer.
Store leftovers covered in the refrigerator for several days. Reheats well.
****I am all in favor of using what you have- you can make this richer and creamier by adjusting the ratio of heavy cream to milk. Don't have heavy cream- use half and half to replace the heavy cream and some of the milk.