Everyone should follow their own custom; many eat dairy foods on Shavuot for various reasons. Some eat the dairy meal specifically on the night of the holiday (Kehillot Yaakov), while others oppose this because even on the holiday night, one should eat meat for the sake of the joy of the Festival (Sha’arei Teshuva, Siman 529). Therefore, those who eat a dairy meal at night should ensure they also consume fish and wine so that it is considered a significant and joyous meal.

Others eat a dairy meal during the day, followed by a meat meal. In such a case, it is necessary to properly separate the two meals. Maran the Mishna Berurah (494:16) ruled according to the Magen Avraham that one may eat both dairy and meat in the same sitting, provided that something is eaten between them to cleanse the mouth. For this, a fruit or vegetable is insufficient; something more substantial like bread or a biscuit is required. Afterward, one should drink water, wash the hands, wait a short while, and then continue with the meat meal even without reciting Grace After Meals (Birkat HaMazon).

However, many authorities disagreed with the Magen Avraham (the Shelah; see commentators on Yoreh Deah, Siman 89) and required reciting Grace After Meals between the two. Yet, this raises a concern of reciting an “unnecessary blessing.” Therefore, the most correct path is to eat the dairy meal, cleanse the mouth, recite Grace After Meals, wait approximately fifteen minutes, and only then wash hands for the meat meal; in this way, the Grace After Meals is not considered unnecessary. We add that according to the Holy Zohar, it is forbidden to eat meat and dairy in the same “hour,” and according to the literal meaning of its words, one should wait an hour or at least the majority of an hour (Shalmat Chaim)