1.ברכי יוסף אורח חיים סימן תצה
Halachot regarding Yom Tov: Making the chocolate dough/paste is prohibited on Yom Tov, even though food preparation is generally allowed, because there is not a change in the way they are made, and it seems like כעובדין דחול an action of chol, work that is normally done on a weekday. The chocolate prep could be done prior to the Yom Tov.
2.קיצור שולחן ערוך סימן לח סעיף י”ב
Shlomo Ben Yosef Ganzfried (1804 – 1886) lived in Hungary; he is also known as the Kitzur Shulchan Aruch after the book he wrote, which is a summary of the Shulchan Aruch with reference to later commentaries.
This section talks about liquor/ intoxicating drinks made from grain or honey that people buy from non-Jews and drink in a store (perhaps a coffee house or tavern) an act that is permitted as long as there is no wine yeast in the beverage. But in a place where people are lenient about drinking wine made by non-Jews, one should also be stringent about drinking an intoxicating drink. In regard to drinking coffee and chocolate and tea made by a non-Jew, one who saves his soul should stay away from that. There are those who allow this, as long as it is an occasional thing and not a daily or regular custom.
3.שו”ת מנחת יצחק חלק ה סימן נח
Question: If a chocolate factory is run by non-Jews, and chocolate made there has fat from a non- kosher source: 1) May you take pleasure from the chocolate by giving the chocolate to a non-Jew? 2) May you cook with that chocolate even if you are not planning on eating it?
Answer 1: Taking pleasure from it: If the mixture (chocolate) was not made by cooking, you may take pleasure from it, even if milk and meat are combined. If the mixture was made by cooking, in a way or quantity that is only substantial according to the rabbis, but not according to Torah, you can probably still say that one could take pleasure from it. If the mixture was made by cooking in a way or quantity that is substantial according to the Torah, then you need to sell it to a non-Jew that you do not know. (the possibility of selling it to a non-Jew you know requires further examination) and you are forbidden from giving it as a gift to a non-Jew.
Answer 2: Re: Cooking it or with it:
If this is a quantity forbidden from the Torah, it is forbidden to cook it because even though it has already been cooked, the second time something occurs to the mixture. If the quantity is only forbidden according to the rabbis, you may take pleasure from it, and cook with it.
Reason: The major issue discussed here is בישול אחר בישול bishul achar bishul, meaning, if something was already cooked, and then it is reheated, does the reheating cook it some more? Or, since it has already fully cooked, the reheating is merely heating it, not cooking it and changing something essential about the food? Two other big questions involve deriving pleasure from something that was cooked with milk and meat. Does the prohibition from cooking milk and meat and deriving pleasure from it. Do they stand alone or do they come together?
4.תשובות והנהגות כרך ה סימן רמט
Question: May jam or chocolate that is made by a non-Jew and is not eaten as part of the meal be eaten or not? Then, a more specific question is asked: Is there a problem with chocolate made by non-Jews in a factory where there is rabbinical supervision which ensures there is no mixture of non-kosher ingredients?
Answer: Not really, but it is better that an observant Jew handles some part of the making of the chocolate, and a Jew should be the one turning on the oven.
Reason: If a Jew is involved in the making of the chocolate, it means that there is a greater likelihood of the kosher requirements being met .
5.פסקי דין – ירושלים דיני ממונות ובירורי יוחסין יא עמוד רמא
These are summaries of verdicts of cases that were brought before the Rabbinic courts in Jerusalem.
This passage mentions that once someone asked his rabbi if he could eat chocolate made in Europe, and his rabbi responded that he should eat bread dipped in wine and sugar instead of eating chocolate.
Another section mentions another rabbi who heard from his father that pareve Lieber brand chocolate (that was made in Israel) may be eaten.
6.שו”ת ציץ אליעזר חלק טז סימן כה
Question: May Israel import milk chocolate from Switzerland, when all the inspections show that the chocolate is completely kosher, even though they cannot have mashgichim in every single dairy farm to overlook the milking process?
Answer: Even according to the stricter views, this should be permitted.
Reason: Since the factory is not really using the milk itself, only the powder that is derived from the milk, and given that there are governmental regulations that prevent the milk from being treif (not kosher), then it is permitted. But the contract should not be signed with the dairy farms, and only with the chocolate factories, so that there is no Jewish involvement or indirect approval of the milking.
Also, since there are mashgichim overseeing the process, even if they cannot be present for the whole chocolate-making process, the knowledge that they can show up at any given moment is enough.