The simple answer is whatever she usually eats, but omit the processed food, wheat, particularly white flour, sugar, pasta, white rice and potatoes that cause the blood sugar and insulin levels to rise quickly, and limit other starchy root vegetables. Pulses, legumes, nuts and seeds are all allowed within the calorie restriction. Her carbs may be higher than for a non vegan, but as long as weight loss is occurring then fat is being burnt, and ketosis is occurring as it should. The diet books themselves may be useful for suggestions as to what alternatives are possible to the ‘white stuff’, but many of us don’t always use alternatives.
I rarely used the set recipes, just adapted my own way of eating like this to be BSD friendly. If you post a couple of typical current vegan meals I can have a go at BSDing them for you, I’ve had a lot of practice and almost do it automatically now.