From π to Pie, 3.14 is the Magic Number at City Colleges


If you consider yourself a math person – or you simply have a sweet tooth – an important holiday has finally arrived.

Celebrated annually on March 14th, Pi Day is both a celebration of the mathematical constant π and the perfect excuse to bake a delicious desert.

As the holiday officially kicks off, we asked Christopher Sabino, a professor of mathematics at Harold Washington College, for quick refresher on all things π (pi), starting with the most important question: What is pi?

If you guessed something like, “3.14, and it has to do with circles,” Professor Sabino says you’re not too far off. Here’s his brief explanation of his favorite number:

“It is a special number, a constant really, representing the ratio of the circumference to the diameter of a circle. For hands-on learners, grab a soup can and two pieces of string. Using one string, measure the distance around the can (circumference, C), and then measure the distance across the top of it (diameter, d) with the other string. You’ll see that the string for the distance around is a little over three times the length of the shorter string used to measure the distance across. This is true for every circle, no matter how big or how small it is. We call that ratio π, and it actually allows us to find the circumference of the circle (C=πd=2πr).”

Professor Christopher Sabino

Like other “irrational” numbers, Professor Sabino says π has an infinite number of digits, and there is no pattern to them. That means that you could take all of your friends’ and family’s phone numbers, line them up into one extra-long number, and, somewhere in the endless digits of π, you would find that exact same sequence of numbers. Currently, over 30 trillion digits have been calculated for π.

If that’s enough math to make you hungry, our experienced chefs at Kennedy-King College’s Washburne Culinary & Hospitality Institute put together a recipe that’s “easy as pi(e).”

Not a chef? Not a problem. Their two-way apple pie recipe, which garners either one classic, double-crusted apple pie or one Dutch crumble apple pie, comes together with just a few ingredients so that any novice in the kitchen can celebrate Pi Day with a fresh baked desert.

Watch as KKC’s Chef Cara Benski-McPhee and her student assistant Ariel Henderson walk viewers through a step-by-step tutorial, and find the full recipe below.

Happy Pi Day!


Ingredients (for one pie):

  • 1 9-inch pie tin
  • 1 package premade pie crust
  • 6 large apples (Chef Benski-McPhee recommends granny smith)
  • 1 cup granulated sugar
  • ¼ teaspoon salt
  • 2 tablespoons lemon juice
  • Milk or egg wash
  • Optional: course sugar for topping

If making the Dutch crumble apple pie, you’ll also need:

  • ¼ teaspoon ground cinnamon
  • ½ cup light brown sugar
  • ½ teaspoon baking soda
  • ½ cup chopped nuts or rolled oats
  • ½ teaspoon vanilla extract
  • 2 tablespoons butter


  1.  Preheat the oven to 375 F (or 350 F, depending on your oven).
  2.  Measure out all of the ingredients and set aside.
  3.  Place one premade pie crust in the pie tin and set aside.
    • If baking the Dutch apple pie:  Crimp the pie dough edges (be sure to watch the video for a tutorial!) and chill for 20 minutes. Prepare the crumble topping by mixing together the cinnamon, brown sugar, baking soda, vanilla, and butter. Add the chopped nuts or rolled oats and set aside.
  1.  Peel and remove the core from the apples. Slice into ½-inch pieces or dice into 1-inch chunks, depending on personal preference.
  2.  Add the sugar and lemon juice to the apples and mix together.
  3.  Arrange the apple mixture in a dome-like pile in the pie tin and cover with the following toppings (depending on which pie you have selected):
    • If baking the Dutch:  Place the crumb topping on top of the dome-piled apples. Make sure to “pack” the topping into the apples, but not too tightly.
    • If baking the classic:  Place the second pie crust on top of the dome-piled apples. Join the two crusts together and crimp the edges of the pie crusts. Wash the pie crust with either milk or egg wash. Optional: Sprinkle the top of the pie with course sugar.
  1.  Place the pie in the preheated oven and bake for 45-55 minutes, or until the crumble begins to melt on the Dutch apple pie and the crust turns golden brown on the classic.
  2.  Allow the pie to cool for two hours before serving.
  3.  Dig in and enjoy the rest of your Pi Day!