Reference for Chullin 216:6

והא איתמר חצי זית בשר וחצי זית חלב שבשלן זה עם זה אמר רב

whence it is clear that the Torah forbade the kid only and not the milk.<span class="x" onmousemove="('comment',' Rab contends that whenever flesh and milk are cooked together in any proportion whatsoever, it is only the flesh that is forbidden and not the milk.');">⁵</span>

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