Pecos Bills is my favorite; both for a TS and for sharing. A double cheese bacon burger coupled with the "fixin bar" is more than enough for two adults with an "average" hunger pain.
Flaming Tree is another great option. The rib meal is great and also big enough to share. I would add either extra beans, corn or fries though.
Cosmic Rays Chicken and Ribs is a FEAST.
What makes Pecos Bills and Flaming Tree great is if you are on the meal plan, you also get a dessert. The chicken and ribs allowed on as a single TS.
Most other TS in Disney have portions large enough to share.
If you will look around other posts, you will find AMAZING ways some DIS Folks have found to save money.
Go forth and be frugal...