Mixing 〜し and 〜ので in an explanation


In the _Genki Chapter 13_ reading section, an exchange student describes going
to a restaurant with her host family and unwittingly eating turtle for the
first time. Her host-father insists it is tasty. Despite feeling uneasy about
eating the mystery meat, she writes:

> でも、お腹がすいた **し** 、おいしかった **ので** 、たくさん食べました。

What is happening with this mix of し and ので? It seems the ので clause has some
sense of "and because it ended up being tasty", while the し clause seems to
relate to her reasoning before she started eating.

