There are restaurants everywhere, in the country side as well as in the villages and in the towns. No matter where you are, you find one, maybe your favorite one!
Places with several restaurants:
Harbour of Porto Cristo (large choice, free parking shortly before entering the harbour on the left side), harbour of Porto Colom (tendecially classy but not only), downtown Manacor (Sa Fonda, Ses Delicies, Mig i Mig and many others, all authentic), Cala d'Or (tendentially touristy, but huge choice and generally good)