by the amazing Ryan NorthI don't love π Day just because I teach math. I mean, that helps, offering an opportunity to highlight and celebrate the playfulness that math can offer, but there's also some degree to which celebrating a transcendental number such as π is an interesting examination of our quest for knowledge. Humans have been aware of π, the constant ratio of a circle's circumference to its diameter, for about 4000 years, since the time of the Ancient Babylonians (who approximated π at 3.125). Since then, a remarkable amount of time and energy has gone into extending and refining how accurately we can describe π, even though the most common approximations — 3.14 and 22/7 — haven't changed in nearly 2500 years, since at least the time of Archimedes, in the 3rd century BCE and even though we've understood that it's irrational and won't end since 1761. There's a somewhat apocryphal claim that it would only take 40 digits of π to measure the circumference of the known universe with a minute margin of error. Regardless of the veracity of that, it does highlight the degree to which the vast majority of the calculated digits of π, patternless, endless and infinitesimally small, are unnecessary for any practical purpose. And yet, we keep calculating further. There is a certain poetry in seeking knowledge purely for its own sake; this is another piece of what we're really celebrating by celebrating π Day.
Also, it's a good excuse for pie: pie and scores of terrible, terrible puns.
I make two pies each π day, because two pie are enough to go around (I warned you about the terrible puns). I like to try a new pie every year for π Day, usually a somewhat fanciful one that I invent, if only so that it's unique among pies. Last year, I decided it was time to take on Snozzberry Pie. Unfortunately, snozzberries aren't in season this time of year (or any other), so what to do in their absence? Examining the answer to that question has much in common with humanity's quest for pi: fundamentally unanswerable, but bears eternal examination, revealing more and subtler nuance over time. Alternately, you can just go with whatever fruit looks good and on sale. The below pie got rave reviews from tastebuds young and old last year. The taste blends into something not entirely placeable, yet pleasantly fruity with a surprise twist, and the filling has just enough starch to hold a soft gel.
Excuse the terrible photo quality.
- 2 pie crusts (for top & bottom, your own recipe or the one below) for filling:
- 1 c. formerly frozen raspberries (they'll be pretty mushy)
- 1 c. fresh blueberries
- 4 kiwis, quartered, peeled and sliced
- zest and juice of one lemon
- ½ c sugar
- ¼ c. flour
- ¼ c. cornstarch
- pinch cayenne (good snozzberries have a little piquancy to them)
Preheat oven to 350 degrees. Mix all filling ingredients in a small bowl. Roll out one pie crust and lay in pie pan. Pour filling in, cover with other crust and crimp edges. Bake for 50-60 minutes or until crust is browned and filling is bubbly.
Pie crustmakes 1 pie crust (you'll need 2 for the recipe above)
- 1 stick cold butter
- 1 cup flour
- ½ tsp salt
- no more than ¼ c. cold water
You can use whatever crust recipe you like for this pie, but this is the recipe that stays in my head, so it's the one I use.
The food processor helped me conquer my timidity of pie crust as it helps avoid getting the butter too warm, working the flour too much and developing the gluten, or taking forever. Cut each stick of butter into 10-20 pieces of roughly equal size. Put that and the flour in the food processor and pulse until the butter is a somewhat gravelly texture. Pour water in a thin stream while on until the dough starts to come together. Dump out onto waxed paper. Gather and squeeze into a ball, then flatten into a rough disk and wrap in its own piece of waxed paper. Refrigerate for at least an hour.
When making more than one crust, you should wrap and chill each individually. I like to do each in a separate batch to keep the amount consistent. If using a food processor, it's not necessary to wash the bowl between each crust. If you're doing multiple crusts old school with a pastry cutter, you may want to cut all the butter into all the flour at once, but I'd still recommend mixing each crust with water individually. After cutting the butter into the flour and salt, take 1½ c. of that mixture and trickle in the water while bringing the dough together with a spoon or your hands. Wrap and and chill individually as for food processor directions.