You may not find great restaurants with hygienic facilities but the local South-Indian food will be good. Small restaurants will be the safest options and will provide you authentic and lip smacking traditional delicacies and maybe even a subtle variety. The typical South-Indian platter consists of Idli, Dosa, Chutney, Vada, Sambhar, Rasam, Upma, Sweet Pongal, Payassam, Kesari.
Here are the top 2 restaurants in Thiruvannamalai: