SCOTT SIMON, HOST:
Next Thursday isn't just Thanksgiving - it's also Hanukkah. And this convergence is very rare and it's been dubbed Thanksgivukkah. Deena Prichep has been thinking about how to celebrate this overlapping holiday.
DEENA PRICHEP, BYLINE: Ed Reingold is a computer scientist who has written about various calendar systems. But he says that you don't really need specialized training to figure the Jewish calendar.
ED REINGOLD: The great medieval sage Maimonides claimed that even a child could learn to calculate the Jewish calendar in a couple of days. Children must have been smarter then.
PRICHEP: The basic confusion comes because the Torah lays out two different directives.
REINGOLD: It is a lunar calendar, and the months are determined by the moon, roughly. But the years are determined by the sun. So, it has to balance these somewhat irreconcilable criteria.
PRICHEP: The solution, which may or may not be obvious to children, is to insert an entire leap month.
REINGOLD: Over a period of 19 solar years, one has to introduce seven extra months. So, that means it's going to be a little more often than every two years, and a little less often than every three years.
PRICHEP: In years that are due for a leap month - like this one - holidays can get pretty early. And when that early Jewish calendar coincides with a late Thanksgiving, well, that's Thanksgivukkah. But now that we've tackled the math, what do we do about the menu?
EMILY FLEISCHAKER: We came up with the list of foods you can't imagine having Thanksgiving without, and you can't imagine having Hanukkah without, and just sort of mushed them together.
PRICHEP: Emily Fleischaker is food editor at the website BuzzFeed. She and her team came up with a full Thanksgivukkah menu. It starts by topping latkes with cranberry applesauce.
FLEISCHAKER: We have the sweet potato bourbon noodle kugel and Brussels sprouts with pastrami.
PRICHEP: They added horseradish to mashed potatoes, and made stuffing out of challah.
FLEISCHAKER: And then the main course is a Manischewitz-brined turkey. It is incredible. It's a little terrifying when you pull it out of the brine and it's bright purple, but it turns out beautiful.
PRICHEP: For dessert, Fleischaker put rye and caraway in the pumpkin pie crust. And ruggelach, those Eastern European rolled cookies, get a sticky, gooey pecan pie filling.
(SOUNDBITE OF PACKAGE RUSTLING)
FLEISCHAKER: Oh man. Oh my god. They have a salty-sweet thing happening, and a lot of, like, different textures. They're the kind of thing you eat one, and then all of a sudden you've eaten five.
EVE JOCHNOWITZ: From the Torah itself, there is the verse that you will come into the promised land, and you will eat and you will be satisfied and you will praise the lord. And that really is the story of Thanksgiving.
PRICHEP: Eve Jochnowitz is a culinary ethnographer who studies the importance of food in Jewish life. And, as with Thanksgiving, a lot does come down to food.
JOCHNOWITZ: The table is the stage on which all sorts of Jewish values are performed. The code of Jewish law is called the shulchan oruch, the set table. And the commentary on that book is the mapach, the tablecloth.
PRICHEP: But Jochnowitz says that setting out way too much food isn't just a Jewish phenomenon; it's an immigrant phenomenon. It can be Jewish grandmothers frying up just one more latke or pilgrims feasting at Plymouth.
JOCHNOWITZ: Food is so delicious, and it's so abundant, and there are so many choices. And we eat, and we are satisfied, and maybe we are even so stuffed that we can't move. And how can we help it? We cannot help giving thanks after enjoying this wonderful feast.
PRICHEP: And this Thanksgivukkah feast is especially sweet because we don't know when it'll happen again. Those leap months reconcile the Jewish calendar, but not perfectly. It's gaining a few extra days every thousand years. If nothing's done to correct this, it'll be about 80,000 years before the calendars line up again. Which is all the more reason to mix up the Manischewitz turkey brine, and make the most of this Thanksgivukkah. For NPR News, I'm Deena Prichep.