I just had a dinner the other week at Olivia's, which by the way is a wonderful hidden gem for all meals!!!, I'm not a vegan, but I do try to cut down on meat and I had an delicious dish, Penne Pasta, with sun dried tomatoes and spinach leaves dressed with a warmed olive oil dressing. It had parmesan cheese on the top, but I'm sure that could just be omitted.
For any meat eaters in the family, the prime rib is one of the best you'll find. We've had this often too. Like I said, it's a wonderful hidden gem with great service, warm atmosphere and delicious food. You can get there easily by boat or bus from Downtown Disney.