Carb question

Rice

If you're talking high carb, high fiber... just about any bean, many peas, oatmeal... quite a few more that are 'moderate calorie/carb' and high fiber, but if you're looking for high carb/low sugar specifically then the beans, peas, oatmeal are the main go to. Probably most things made with stone ground wheat or oats as well IF you can make them yourself without sugar or buy ones that aren't particularly high in it (lot of breads have lots of sugar added for taste reasons.) You could also look at some of the gluten free breads that are made with Flax & Almond Flour... those often have staggeringly high fiber.