Bittul by basar b'chalav

I argued earlier this week that when you cook basar b'chalav and there is no ta'am that is not a halacha of bitul (which means there is an issur which is nullified), but there is simply no issur because "derech bishul asra torah" and cooking with no ta'am is not called bishul. If so, I was stumped because this leads to the conclusion that there should be no din of "ain mevatlin issur l'chatchila" by mixing a drop of milk into meat.
I thank Chaim Markowitz for pointing out that this exact argument is made my R' Akiva Eiger, Shut Mahadura Kamma #207. Baruch she'kivanti!