Reference for Shabbat 267:6

ת"ר אין מסננין את החרדל במסננת שלו ואין ממתקין אותו בגחלת א"ל אביי לרב יוסף מאי שנא מהא דתנן נותנים ביצה במסננת של חרדל

he replied. 'Nor sweeten it with a glowing coal'. But surely it was taught, One may sweeten it with a glowing coal? — There is no difficulty: one refers to a metal coal, the other to a wood coal.<span class="x" onmousemove="('comment',' The latter is forbidden, as it is extinguished in the process, which is prohibited on Festivals. ');">¹¹</span> Abaye asked R. Joseph: Wherein does it differ from [roasting] meat on coals?<span class="x" onmousemove="('comment',' Though this puts them out. ');">¹²</span>

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