Okay, the user wants me to translate "irish butter" into Simplified Chinese. Let me check the rules again. The first rule says to translate all content into Simplified Chinese. The second rule states that if the content is already in Simplified Chinese, output it unchanged. The third rule is to provide only the translation result with no explanations.
So, "irish butter" is in English. I need to translate it. The direct translation would be "爱尔兰黄油" because "Irish" is "爱尔兰" and "butter" is "黄油". I should make sure there's no existing Simplified Chinese version here. Since the original is in English, I don't need to leave it as is. Just translate it. Also, the user wants only the translation, no explanations. So the response should be "爱尔兰黄油" without any extra text. Let me confirm there are no other possible translations or nuances. I think that's straightforward. Alright, that's the answer.