Actually, it appears that "asar" is used in Spanish as "grilling/roasting" both in the cooking sense and in the sense of being asked questions or spoken to in an intense manner.
This may be where Tagalog took the meaning. Tagalog doesn't use it in the form of cooking, but in the other form.
www.spanishdict.com/ translate/asar
Transitive definition #2: "to bother"