Dairy On Shavuot

A few points on the custom of eating dairy on Shavuot.
The Rama says the reason for the custom to eat dairy on Shavuot is a זכר לשתי הלחם.  In his words: ונוהגין בכל מקום לאכול מאכלי חלב ביום ראשון של שבועות ונראה לי הטעם שהוא כמו השני תבשילין שלוקחין בליל פסח זכר לפסח וזכר לחגיגה כן אוכלים מאכל חלב ואח"כ מאכל בשר וצריכין להביא עמהם ב' לחם על השלחן שהוא במקום המזבח ויש בזה זכרון לשני הלחם שהיו מקריבין ביום הבכורים:
The Rema says the custom is on the first day, does that exclude the night and the second day?
According to the Rema the custom wouldn't be to just eat ice cream or have some milk, there has to be bread with it.  I guess that can be fulfilled with mezonos, such as cheese cake.  Based upon this Rav Chayim Shalom Deutsh raised a question in hilchos berachos.  Often many in cheesecakes the mezonos is there only as a support to hold the cheese, in which case no beracha is recited on it and one only recites a shehakol on the cheese.  On Shavuot though, one might want the mezonos to fulfill the custom of the Rema and in which case it wouldn't be טפל and one would recite mezonos, a lot of variables that can be thrown in the question, וצ"ע.

For the spelt lovers out there, the Magen Avrohom (494:8,) cited in Mishna Berurah (#17,) says based upon the Rema that we eat dairy as a זכר לשתי הלחם, that the bread must be wheat as well just like the לשתי הלחם.  By extension we may add one should eat fine wheat, not whole wheat.

The Mishna Berurah (#12) brings an additional reason (I will cite his words in English.) "I also heard in the name of a Gadol who said a correct reason for this: that when Bnei Yisrael stood at Har Sinai and accepted the Torah(When the 10 commandments were revealed, and through this all the parts of the Torah were also revealed to them, like that Rav Sadya Gaon writes, that the 10 commandments sustain the whole Torah) and they went down from the mountain to their homes they found nothing to eat immediately except for dairy foods because for meat they would need much preparation to slaughter with a checked knife like Hashem commanded... And to clean out the strings of forbidden fats and blood, and to rinse and salt(the meat). Also to cook in new vessels because their previous vessels had been used to cook meat (that they now discovered was actually trief) had been used in the last 24 hrs (which is what is forbidden Biblically) so their old vessels were forbidden to them, therefore they choose on account of the time to eat dairy foods and we do this as a commemoration of this."  Rav Zeven in footnote 41 of מועדים להלכה on Shavuot points out that since the Torah was given on Shabbos they couldn't slaughter animals etc. anyway, nothing to do with the new laws.  In some versions of Mishna Berurah they say that the explanation based upon the new laws is only necessary according to the Pirkey D'Rebbe Eliezer that holds the Torah was given on Erev Shabbos.

Another one of the reasons given for the minhag to eat dairy is based upon the midrash tehillim (8) that the angels complained how could the Torah be given to mankind a second time if they just messed up with the agel?  Hashem said well you aint so perfect either for in the few minutes you came down in a bodily form you ate בשר וחלב at Avrohom's house.  Since, the whole reason we received the Torah is in merit of the dairy with the meat, we eat dairy as well.  This whole midrash needs an explanation, what is Hashem's answer, you yourselves ate בשר וחלב; how is that an answer to the argument of the angels that you see man is incapable of keeping the Torah?  Furthermore, where does it say the angels ate בשר וחלב, the possuk in Vayera says they ate the dairy first and the meat second, that is permitted and if it was real בשר וחלב how could Avrohom feed it to them?  In the sefer Pardes Haaretz by Rav Yeshiya Horowitz he cites a teaching from the Alter Rebbe to explain this midrash.  The Alter Rebbe explains that the reason בשר וחלב is prohibited is because בשר  is גבורה and חלב is חסד and they can't be mixed.  Why can one eat meat after dairy but not vice versa?  He explains because the halacha is תתאה גבר, it is what is eaten first, that which is in the bottom of one's stomach that has the dominant force.  Hence, if one eats dairy first, the חסד wins over the גבורה of the meat that follows so its permitted.  In reverse, meat first, then its גבורה will overpower the חסד of the dairy and that is prohibited.  Based upon this he says, that is all true if תתאה גבר, if עלאה גבר then eating meat after dairy would be prohibited.  That was Hashem's answer.  Since you ate meat after dairy, you proved you hold תתאה גבר, if that's the case, the Torah should be given to the תתאה, to mankind. [The basic kabbalistic approach to explain the midrash is also in Pardes Yosef Vayerah (#21) in the name of the Yid Hakadosh.]  The point of mattan torah was to enable תתאה גבר ,that man should be able to effect kedusha into the world.