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Yes, Pi Day. Pi, as in π or 3.14. Why is it Pi Day? It’s March 14th, or 3/14, hence, Pi Day.
Why am I so excited about Pi Day? Well, in my life BK (Before Kid) I was a high school math teacher. Geometry is my favorite subject. To be more specific, I love proofs. Yes, I’m weird. I even had a license plate that read I TCH PI. I even have a shirt.
brownie pies decorated with pi symbol on white platter
So, on March 14th each year I celebrate Pi Day. And that means…eating pie! (Someday I want to go to the Exploratorium in San Francisco on Pi Day. At 1:59 they do a parade. Google it.)
Of course, since I’m blogging now, I needed a good pie recipe to celebrate. I also have an overabundance of Girl Scout cookies in my freezer (my daughter is a Daisy). I love the Thin Mints. If I’m not careful I will eat an entire tube of them. By myself. In less than 20 minutes.
Thin Mint Brownie Pie. Does it get better than that? And it’s super simple too. I used a boxed brownie mix with my homemade crust recipe.

I decorated the tops of my pies with white chocolate pi symbols. I melted the chocolate in the microwave and piped it on using a pastry bag. Serve with ice cream or whipped cream and more Thin Mints!

I had extra brownie batter so I made a round brownie too.


In addition to dessert pie, Pi day cannot be celebrated without eating all things round and pie. That means Ritz Crackers for snack. And pizza for dinner. My daughter is having a peanut butter sandwich cut into a circle in her lunch box, and a round cookie for dessert. Pancakes for breakfast, too. We’ll probably do some fun round math activities (suitable for Kindergarten) after school and before bed we will read Sir Cumference and the Dragon of Pi (by Cindy Neuschwander).
Want some other ideas to have your own Pi Day celebration? Here are some links to some awesome round recipes I’ve posted in the past:
Chicken Biscuit Pot Pie
Enjoy your Pi Day! Eat 3.14 slices of pie for me!
(Yes, I’ll forever be a math dork. But I’m proud of it!)
Thin Mint Brownie Pie


For the Crust:
2 1/2 cups flour
1/2 teaspoon salt
1 cup (2 sticks butter), cut in small cubes and chilled
1/2 cup ice water

For the filling:
1 box of brownie mix (family size), plus the ingredients on the box
1 sleeve (half a box) of Thin Mint cookies, about 20
(If it’s not Girl Scout Cookie season, you can use the Keebler Grasshopper cookies.)

To prepare crust:

  1. Mix flour and salt in a food processor. Add chilled butter and pulse until it forms coarse crumbs. Add the water, 1 tablespoon at a time, until the dough forms a ball. Separate into two sections.
  2. For mini pies: roll out one section of dough to 1/4 inch thick and cut circles that are 4 inches in diameter. Grease your muffin tins or spray liberally with cooking spray and press into each muffin cup. (A silicone muffin pan works awesome for this; they pop right out. Be sure if you’re using a regular muffin tin to really grease it good or they will stick. And you’ll end up with chunks of pie.) Repeat with the remaining dough, re-rolling when needed. Makes approximately 18-22 mini pies. Chill until ready to use.
  3. For a large pie: this dough recipe will make two 7-9″ pie crusts. Roll out dough and line the two pie pans. Crimp the edges. Chill until ready to use.

To prepare filling:

  1. Preheat oven to 350 degrees.
  2. Mix the brownies in a large bowl following the directions on the back of the box.
  3. In a food processor or on a large cutting board, finely chop the Thin Mint cookies and add them to the brownie batter. (If you stopped here and just made these as brownies they’d be awesome!)
  4. Pour the brownie batter evenly into your mini pies or large pie crusts. You may have some filling left over. You can bake this in greased muffin tins or a small baking pan.
  5. Bake mini pies for 18-22 minutes. Bake large pies about 25-35 minutes. (I made mini pies not a large one, so after about 20 minutes keep an eye on the oven so they don’t overcook.)

Best served with whipped cream or ice cream and lots of extra Thin Mint cookies!

Source: Crust recipe from All Recipes; idea by Dorothy @ Crazy for Crust

Last Updated on May 16, 2024

Dorothy Kern

Welcome to Crazy for Crust, where I share recipes that are sometimes crazy, often with a crust, and always served with a slice of life.

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  1. Wow. My Jonila (daughter) find this and crazy to taste it. its more then awesome. i am baking it now. why you not make videos for us. ?

  2. At the school I went to and then later taught at, we ALWAYS celebrated Pi Day. Every year. Our school closed two years ago, so reading this today made me very happy!

    And this recipe looks amazing. Lucky for me there is a box of thin mints in the freezer =)