Yes, you can eat yellow rice during a Thursday fast, and in fact, it is often offered to the deity being honored on this day.
The provided reference states that offering yellow rice to the Lord is considered auspicious during a Thursday fast. This suggests that not only is it permissible to eat yellow rice, but it is also a recommended offering and part of the fasting ritual. The emphasis is on offering it to the deity first, after which it can be consumed. The yellow color is associated with the deity and is considered auspicious.
Therefore, the answer is definitively yes, eating yellow rice is allowed, and even encouraged, as part of a Thursday fast after it is offered to the deity.
