Mathematically Impossible Pi

There are “math people,” and then there’s everyone else. Math people breeze through tabulations for group dinners, factoring in precise tip percentages and taking individual drink orders into account, while the rest of us are still fumbling to pull up the calculator app on our phones. Math people relish real-life opportunities to crunch numbers when others can only feebly chew on their finger nails. To me, those skills are a sort of magical, superhuman power that I can only admire from afar, left behind in the dust as soon as we advance beyond basic multiplication and division. Needless to say, I am NOT a math person, but for the enviable folks who are, this day is for you.

Pi Day, March 14, 3.14, is the most mathematically sound day of the year to indulge in a slice of pie. At least that’s what the experts seem to say, and with my shaky analytical understanding, who am I to question the specifics?

Anything beyond the most basic math is an impossibility in my hands, but despite the name, this pie is not. The title merely refers to the way it “impossibly” forms its own crust as it bakes, no pastry needed to support a luscious custard filling. Riffing off my favorite childhood sandwich, stacked thick with gooey marshmallow cream slathered over crunchy peanut butter, this reinterpretation skips the bland bread and gets right to the good stuff. Deceptively simple, it takes little more effort to assemble than the classic school lunch inspiration itself.

Prepare for a decadent peanut butter and marshmallow onslaught; just a small slice will satisfy the most intense cravings, and it doesn’t take a math person to figure that out.

Yield: Makes 8 - 10 Servings

Impossible Fluffernutter Pie

Impossible Fluffernutter Pie

No crust needed to support these rich slices stacked thick with gooey marshmallow cream slathered over crunchy peanut butter.

Prep Time 5 minutes
Cook Time 55 minutes
Total Time 5 minutes


  • 1 Cup Crunchy Peanut Butter
  • 1/2 Cup Vegan Vanilla Yogurt
  • 1/2 Cup Plain Non-Dairy Milk
  • 1 Teaspoon Apple Cider Vinegar
  • 1 Teaspoon Vanilla Extract
  • 3/4 Cup Dark Brown Sugar, Firmly Packed
  • 1/3 Cup All-Purpose Flour
  • 1 Tablespoon Arrowroot Powder
  • 1/2 Teaspoon Baking Powder
  • 1/2 Teaspoon Salt*
  • 1/2 Bag (5 Ounces) Vegan Mini Marshmallows
  • 1/2 Cup Roughly Chopped Roasted Peanuts


  1. Preheat your oven to 350 degrees and lightly grease a 9-inch pie pan.
  2. Whisk together the peanut butter, yogurt, non-dairy milk, vinegar, and vanilla in a small bowl, and set aside. Separately, combine the sugar, flour, arrowroot, baking powder, and salt. Mix thoroughly so that no lumps remain and all of the dry ingredients are completely incorporated. Add in the liquid mixture and stir until smooth.
  3. Pour the batter into your prepared pie pan, and bake for 40 – 45 minutes. It should be set around the edges but quite wobbly in the center, much like a cheesecake. Pile the marshmallows on top in an even layer and return the pie to the oven. Set the broiler to high and cook for just 5 – 10 minutes, until the marshmallows are lightly toasted and golden brown.
  4. Let cool to room temperature before garnishing with peanuts, slicing, and serving.


*If you’re using salted peanut butter to begin with, dial back the additional salt or omit entirely, to taste.

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26 thoughts on “Mathematically Impossible Pi

  1. Oh, my, Hannah, I’m pretty sure my husband would love this! We’re both math people to some extent, he more than I. But it’s no problem figuring that this adds up to a winner. ;-)


  2. A much more interesting kind of pi than the one maths geeks are obsessed with.
    I’ve always been able to do anything with numbers, but show me a,b,c = x,y,z and a load of funny squiggles and my mind goes blank.
    Maybe that’s why I made enough money to retire at fifty :)

  3. This looks delicious Ms Hannah. I think I might even be able to get most of the ingredients in this one! I am NOT maths minded but all of my children are (go figure!) I think I will stick to this kind of pi rather than tax my brain with equations and fractions. Cheers for the delicious share for Pi day :)

    1. Now that’s the real reason you have children in the first place, right? ;) Since the only babies in my immediate future seem to be those of the four-legged and furry variety, I just may need to borrow yours for their mathematical prowess!

      1. Any time you want to take advantage of their brains, let me know. I will harness the potential and send it on over the pond ;)

  4. This does look extremely delicious Hannah… And it looks wonderful.. Hope all is well with you too my friend.. :-) and great to see this post today…
    Love and Blessings
    Sue xxx

  5. I was in math class on Pi day and to say the least I was not happy to be there because we were studying for our exam for the next class period. Unfortunately I didn’t get to eat any pie that day either but your pie looks delicious and I want some. I like your post too. If you would follow me or check out my blog I would greatly appreciate it. Either way thank you for your inspirational post. -bel

  6. According to my calculations, your pie is perfectly designed to become a favorite for any occasion. Peanut butter and marshmallows add up to delicious!

  7. Amazing .. I’ll bookmark your blog and take the feeds also? I’m satisfied to find a lot of useful info right here in the post, we want develop more techniques in this regard, thanks for sharing. >

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