The phrase "eating humble pie" is an expression that means admitting to a mistake or wrongdoing. It is often used in a context where someone has to apologize or make amends for their actions. The origins of the phrase can be traced back to medieval England, where the pie was a symbol of a wealthy and prosperous lifestyle. Eating humble or lowly pie was therefore a symbol of humility and submission, which is why the phrase came to represent admitting one's mistake. The phrase "which sort of pie" is sometimes used in a humorous or ironic way, as if the speaker is asking which type of pie they should eat to make amends for a particular mistake.