please try to do this way

Take 3 lemons ,slice them , put it with some pepercone into the pot with some amount of water, put the pot in oven ,325 degree, bake for 1.5 hours ,please don't throw the lemon and water right away, leave it for 24 hours.

Usually once you finish cooking ,please don't leave the food too long in this kind of pot ,because it has a lot of pores in the pot, they are very easy to absorb all kinds of flavor from the food if you leave the food too long in the pot. if you can't finish the food right away, take it out ,and put the left over food into any glass container or porcelain container , then wash the pot immediately . For the best result, soak in baking soda water or lemon water for a few hours , if the food has been used a lot lot of herbs or seasoning during the cooking. after cleaning , you have to let it completely dry, really really dry, you have to let all the pores get dry too. Most of time, I leave it nearby the window to blow dry over night if the weather is not so cold, then I put some clean and dry paper towel in the pot to absorb some possible left over smell ,put the cover on the pot ,then store it in closet .

This is the way how I take care of all my earthware cooking pot, I hope it could help you somehow.