Why would you want to cook kitniyos in your Pesach-dig pots?
Because kitniyot is not chametz, and it’s certainly permissible. In fact, our home will be KFP a week before the chag begins, and will will hot meals made with kitniyot for that week. No muss, no fuss.
Quoting Rav Aviner, shlita, regarding an Askenazi eating in a Sfardi home on Pesach:
Q: I am Ashkenazi. Is it permissible for me to spend Seder night at the house of a Sefardi who eats Kitniyot?
A: Yes, but don’t eat Kitniyot. It is permissible, however, to eat: food which touched Kitniyot, food which absorbed Kitniyot, food in which the Kitniyot are no longer recognizable and are nullified in a majority, and food cooked in Kitniyot pots and pans (Shut She’eilat Shlomo 3:141).