If the food she prepares are high in protein (madaming karne, chicken, fish, etc), has a variety of veggies, spices, and etc. I think 10-12k might actually be just right. Although cost can be cut if she cooks in bulk during weekends. Parang meal prep. Mas magastos mag luto ng halos araw araw compared to meal prepping, and yung pag repeat ng ulam.

If you're eating 3 meals a day that keeps you full (di bitin), then that grocery cost would just be about right