There is really no need to feel overwhelmed by a three-day Jewish holiday. Preparing for a long Jewish holiday, such as when Rosh Hashanah is followed by Shabbat, simply requires some good planning and creative thinking. These three-day Rosh Hashanah menus and recipes are designed for busy cooks who, despite limited time and energy, want to serve healthy, economical, and festive holiday meals. When you map out the days and meals as below, you can see that you only need to prepare food for two or three meals ahead of the holiday. The rest of the meals can consist of leftovers or food you can prepare during the holiday.
Most people prefer to prepare food before the holiday—even when it is a three day holiday—so that the holiday will be more restful for them. Generally, religious Jews who observe Jewish laws are even more likely to finish cooking before the holiday as they can't turn electricity (such as ovens) on and off during the holiday. On Rosh Hashanah, Passover, Sukkot, and Shavuot, however, religious Jews can "pass fire" from a candle to a gas stove top to cook. In addition, they can perform a ritual called Eruv Tavshilin to prepare their Shabbat food during the holiday.
First Night Dinner
This Rosh Hashanah dinner, assuming you have invited guests, includes a variety of traditional holiday dishes.
First Day Lunch
This light Rosh Hashanah lunch assumes you are still full from last night's holiday dinner and you are expecting another festive dinner in the evening. If you want to add to it, you can also serve leftover brisket and chicken from last night's dinner.
Second Night Dinner
Second Day Lunch
Assuming there are plenty of leftovers and there is cooking to do for Shabbat, this meal can consist entirely of food left over from the above three meals.
Third Night Dinner
Given two days of heavy meat meals, it is nice to have dairy meals on the third day. Before the holiday, you can prepare and freeze some quiches. On the second day of the holiday, you can cook fish in a skillet, boil pasta for the kids, and prepare fresh salads. And dairy meals means you can serve ice cream for dessert!
Third Day Lunch
You might be able to get them to sit at the table on the third day of the holiday, but good luck trying to get them to eat. I believe that dairy leftovers from the previous night's dinner will be more than enough for this holiday meal.