Is the Basmalah prescribed when reciting each of Surat Al-Ikhlas, Al-Falaq, and An-Nas in the morning and evening remembrances, or is a single Basmalah at the beginning sufficient?

It is recommended to recite the Basmala at the beginning of each Surah, especially when repeating them, as that is the most complete and best way. The Mu'awwidhatayn (Surahs Al-Falaq and An-Nas) must be recited in their entirety with the Basmala, because the command to recite them necessitates it. However, if you recite the Surahs without the Basmala, there is no harm, as some jurists and reciters have held that the Basmala is not part of the Surah.