We always get a whole grilled chicken and use for a dinner and sandwiches later. Stateside you can buy packaged mix of dry pasta and sauce-- Knorr makes a good alfredo one-- package fits easily in carry-on. Drive by a lolo and take back to your room.

If you were in the Maho area there's a small market right at the rotary that has a hot bar for take-away meals.

Someone mentioned Shop N Drop but there's a minimum order so that option may be too much for you unless you're staying a couple of weeks.