Not-Your-Mama's Tuna Casserole
All amounts of cheese and the half-and-half are approximate, because I didn't measure when I made this up last night. Use what feels right to you. You want to add enough of the liquid so that the casserole isn't gluey when it's finished, but you don't want it soupy, either.
You could substitute chicken broth or milk for the half-and-half if you prefer.