You'll be surprised to find that there is quite a variety of kosher food products in the local grocery stores!
A large selection of Kosher food is found in the upscale grocery called 'Fresh Market'. There is one location a 10 minute drive from the Atlantis Resort and another one which is a 20-minute drive from the Baha Mar Resort (5 min from the airport).
They have a FULL Kosher section of both frozen and dry items. Including frozen chicken bottoms and breasts, steaks, ground meat, Kedem grape juice, Challah, Bissli, Bamba, chocolate, Kosher Milk (non Cholov Yisroel) etc.
They also carry a huge selection of US brand foods and much of it is Kosher.
There is no Kosher restaurant or Kosher catering service in the Bahamas.
The Baha Mar resorts (Hyatt/SLS/Rosewood) can order from Miami Kosher fresh meals for your visit, 14-day notice is necessary.
The Atlantis Resort offers frozen Kosher meals.