If a woman was reciting Birkat Ha’mazon after Se’uda Shelishit on Shabbat, and she realized immediately after reciting "Boneh Yerushalayim" that she had forgotten to recite "Reseh," she should just continue with Birkat Ha’mazon. A man in this situation should recite at that point the special blessing of "Baruch Ata Hashem Asher Natan Shabbatot" (which is printed in many Siddurim). When it comes to a woman, however, since women’s obligation to recite Birkat Ha’mazon is not as certain as men’s obligation, in such a situation at Se’uda Shelishit she should simply continue reciting Birkat Ha’mazon, and she does not need to recite the Beracha of "Asher Natan Shabbatot."
