Luckily, there was much more to eat than that. Lots of plantains and bananas in all forms but mostly fried, fruits and fruit juices, varieties of fish, meat (chicken and pork, cecina, being the most common, but also venado, deer), juanes which is basically rice and meat (or chicken/shrimps) cooked in a banana leaf, and very delicious organic ice creams made of local fruits or raw cacao.
On our first night in Tarapoto, we ate in a restaurant called Doña Zully, which is located right at the Plaza Mayor and offers local specialities. We tried some fried yuca for a starter, and it came with three different but all more or less spicy sauces: huacatai, huancayina and the third was kind of a pickles made of cocona fruit and chili pepper.
The service was very professional and for a price, 46 soles (for two!) the plate was well worth trying.
We drank cocona juice, a new fruit I discovered on that trip. It is said to taste (and look) something like a mix of lemon and tomato and I second that description. I would not qualify it as my new fruit favorite, but in the hot weather a jar of ice cold cocona juice was very welcome.