For me, snuggles with those belly rubs and praise is always nice. I have a hard time seeing my own growth, so pointing out how/where I'm getting bigger is also nice...sincerely or in a teasing manner, either way works.
After a stuffing session, I like to heap on the praise. Tell him how happy I am with him. How well he did for me. This is especially important if I made him go hard or I was particularly mean. Just make him feel warm and fuzzy until the inevitable food coma takes him.