We have a winner - but you are from Brazil so that gives you an advantage. These are indeed cuy which are apparently a delicacy in Ecuador. Most simple meals (chicken, rice, and salad) are around $3 but cuy was $17.
For those not familiar with cuy (as I was) - let me just say that those are particularly large guinea pigs.
Finished the circumnavigation in early February in Grenada. Have to work on a book project for the next several months so the boat will be waiting for next year.