TT #217 · Parashas Reeh · Fourth Aliyah · Passuk 14:21
You shall not eat any carcass; give it to the stranger within your gates, that he may eat it, or sell it to a foreigner; for you are a holy people to Hashem your God. You shall not boil a kid in its mother’s milk.
Torah Temimah points to Torah Temimah.
Sefaria — Torah Temimah on Deuteronomy 14:21
English: “For you are a holy people… you shall not boil a kid” — just as there it is forbidden, so here it is forbidden.
Hekesh / comparison of holiness verses (TT).
The parallel holiness language confirms the basar be-chalav prohibition here.