Can you please settle an argument? If a non Jewish person cooks a meal in a kosher kitchen adhering strictly to the rules of kosher - is the meal prepared still kosher?

Shalom, Firstly let me send you a blessing of peace, and hope that you don't get into any more arguments - discussions are great, but arguments can be nasty! But if you are having them anyway, this seems like a good thing to argue about - rather than who won the World Cup in 1956 - as we can at least learn some Torah from it. As you wrote to this site to ask a rabbi for an answer, you can probably guess that the answer is going to be "it depends...". There could be two problems with the situation you described. The first is the law called "bishul akum", which means non-Jewish cooking. The rabbis made a decree against eating certain foods cooked by a non-Jew. This was in order to limit the chances of intermarriage, and so was only decreed on important foods. That is, if a non-Jew cooks food that is "fit for a king", and it is food that cannot be eaten in its raw state, it becomes forbidden for a Jew to eat. Of course there are many rules about which foods come under this law, but a cup of coffee, for example, is allowed, as it is not considered so important as to be "king's food". Also, if a Jew takes even a small part in the cooking, such as turning on the flame, or stirring the pot, the prohibition does not apply. There is much I could expound on this topic, but this is the general picture. So in answer to your question, it depends on what food is being cooked, and who turned on the fire etc. But, yes, the food cooked by a non-Jew could be kosher, but then again, it could well not be. Secondly, there are certain situations where we would perhaps doubt the trustworthiness of someone who does not keep kosher to vouch for the fact that the food is in fact truly kosher. There are ways to ensure that the food is kosher. However, if we only have the word of the non-Jew who may be a very trustworthy person, but might not take the law as seriously as a religious Jew does (because they are not obligated in kashrut), we would have questions as to the kashrut of the food. Again - this can be avoided, for example by having a religious Jew pop in to the kitchen from time to time (this is one reason they have kosher supervisors in kosher restaurants). So, getting back to your question, it depends on the situation of supervision (and some other factors) as to whether we could eat the food cooked by the non-Jew. I hope this has helped you - and as you guessed, you are both somewhat correct! Blessings.