Sattva is one of the three qualities recognized in Ayurveda, India's ancient whole body approach to medicine and healing, with the other two being Rajas and Tamas. According to Ayurveda each and every being and thing has a balance of these three gunas. In the simplest terms, the three gunas can be described as follows:
Sattva is the quality of balance, harmony, purity, and constructive.
Rajas is the quality of passion, activity, movement, and sometimes restlessness
Tamas is the quality of imbalance, chaos and disorder
Sattvic food is then food that helps promote a state of balance, harmony, and purity. Sattvic food is generally easy to digest, soothing, nourishing, and promote a quiet steady state of mind. In yoga, we're hoping to spend the most time in a mostly sattvic state. By eating sattvic foods along with other activities, we help to cultivate a sattvic state within us.
In general sattvic food is vegetarian and focuses on un- or minimally processed food prepared with love. These include fresh fruits, vegetables, legumes, nuts, seeds, and dairy products so long as they are fresh and from an animal who has not been harmed. A sattvic diet avoids onions, garlic, nightshades, overly spicy food, overcooked or reheated food, and preserved food.
While I don't maintain a strict sattvic diet, I've found that I am a more peaceful and quiet person when I adhere to the sattvic diet as much as possible. To that end, on this site, you will only find vegetarian dishes and the main focus is on sattvic foods. I cook mainly without onions and garlic (an idea that shocked me at one time) and I bake without eggs. As with most obstacles, what once seemed strange is now common and what once was a barrier is now an opportunity. If you have questions about ayurveda or a 'yogic' diet- please ask! And share! I'm still learning!