The highest calorie density is in oils and fat. I am not sure if you are making yogurt but you could make a SCD yogurt (no lactose) out of 1/2 and 1/2 or wipping cream. It tastes amazing and is super high in calories. Coconut oil is very healing and high in calories. This can be added to dishes, used to cock with or even added to a smoothie, with some of the yogurt. Avacados as mentioned are very good also.
Nut flour or coconut flour baked goods might help. The attached link is to a chocolate cake that you should be ok with that looks amazing.
http://health.groups.yahoo.com/group/BTVC-SCD/message/65948
Peaople are raving about these peanut butter cups if you can take nuts
http://health.groups.yahoo.com/group/BTVC-SCD/message/74204
Although honey can be quite high I would be careful there as many folks react to the carb spike (like me).
Dave