The more you use the product the more 'cured' it will become and better it gets.
You can use terracotta on gas & electric hobs, barbeques and in all types of ovens including Agas and microwaves, it is safe up to 250°C. Raise the heat gradually. Take care when using on a ceramic hob to avoid scratching the hob.
Terracotta is a very good conductor of heat and requires relatively little heat, always use low heat with large diameter dishes.
Avoid sudden changes in temperature and never heat an empty pan, however it is OK to heat cooking oil before adding your ingredients.
* Please note that rectangular dishes and those dishes with a diameter of less than 15cm should not be used on direct heat. Use of a diffuser or the largest hob size is recommended for large tagines and bowls.