What is the status of food cooked by a non-Jew who subsequently converted? Is it assur to him and others as bishul akum or not? The two reasons of bishul akum do not apply to a ger, as he knows no assur food was mixed in, and there is no concern of intermarriage. The poskim have a machlokes.
Some hold the food is mutar, as the issur takes effect on the food when it is eaten, not when it is cooked, and at that point, the reasons for the issur do not apply, as mentioned; this is not included under the rule of לא פלוג (שו''ת אבני זכרון סי' ס''ח אות א', משנת הגר פי''ב אות מ''ז ).
However, most poskim hold the food is assur, as the issur most likely takes effect when it is cooked; once it becomes assur, it can never become mutar. Although the reasons do not apply (see above, 21), this is included under Chazal’s broad issur with the rule of לא פלוג (בין ישראל לעמים פ''ה ס''י, גירות כהלכתה פ''ח סט''ו בהערה, וכך קיבל תי ממו''ר בעל קנה בשם בע ריכת גירות ).
