re gentile food establishment

Question

Picking up on the message exchange below, is the difference between pots and ovens? I.e., one cannot eat something cooked in a taref pot, even if the item itself is only comprised of kosher ingredients, but a taref oven is treated differently? Otherwise, I'm not sure how to interpret your response of 7/4 on "supermarket bakery" and your response to my earlier inquiry re non-kosher restaurants. Many thanks. ----------------------------------