Sweet Potato Pie
Adapted from The Joy of Cooking

You can substitute sweet potatoes (or yams) for pumpkin in any pumpkin pie recipe. This page has one delicious recipe.

First, let's clear up some confusion about how sweet potatoes and yams are related. The truth is, they are the same thing-- at least in the United States. This is because "Garnet Yams", "Jewel Yams", and "Beauregard Yams" are the most popular American varieties of sweet potato. This is different from Africa, where the word "yam" refers to a completely different kind of plant. But on this web page, we will stick to the American definition: a "yam" is a variety of sweet potato.

Second, you may be wondering how to cook sweet potatoes. The answer is: any way you want! Sweet potatoes can be boiled, roasted, or microwaved. (They can even be french-fried, but it is hard to make them crisp.) When a sweet potato is completely cooked, it will be soft all the way through. It will yield when you apply finger pressure to it, and a fork will easily pass through it. If you boil a sweet potato, it will fall out of its own skin. If you roast it or microwave it, you may notice a sugary fluid accumulate in your pan or dish. This is normal; the juice may even caramelize with further cooking.

At sea level, it takes 35 to 50 minutes to boil Number 1 size sweet potatoes. Medium potatoes take less time; Jumbo potatoes take more time, unless you cut them up before cooking. Roasting takes more time; microwaving can take less time for smaller or fewer potatoes. Microwaving is most convenient for one or two potatoes; boiling is most convenient for more potatoes.

Here is my recipe for sweet potato pie, as adapted from The Joy of Cooking, by Irma Rombauer and Marion Rombauer Becker. It makes a 9-inch single crust pie:

• Line a pie pan with:

  A pie dough

  I like to use a graham cracker crust.
  The Keebler brand is convenient and produces a mildly sweet, yet crispy crust.

• Preheat oven to 425 degrees Fahrenheit (220 degrees Celsius).
• Mix the ingredients in parts, to get the solid-to-liquid ratio right.
  (The ideal mixture is about as stiff as whipped cream or beaten egg whites.)
  I usually use only 80% to 90% of the liquid ingredients, and most of the flour.
  Mix until well blended:

  2 cups cooked sweet potatoes

  I tend to use a little more sweet potatoes-- about 2 1/4 cups.
  Try to pick out only the best sweet potatoes, without any dark blemishes
  or soft spots -- or at least cut them out before cooking,
  because they can affect the flavor.
  One pound of sweet potatoes yields one cup of cooked sweet potato,
  because you have to remove the skin and pack the rest into your measuring cup.
  (In metric, 1 kilogram of raw sweet potatoes yields 530 ml of cooked potatoes.)

  1 1/2 cups (350 ml) undiluted evaporated milk

  I usually use only 1 1/4 cup (300 ml) evaporated milk,
  to get the mixture right.

  1/2 cup (120 ml) eggs

  Rombauer and Becker call for "2 slightly beaten eggs",
  but I prefer to use 1/2 cup (120 ml) of "Egg Beaters"-brand fake eggs.
  I usually use only 7/16 cup (100 ml) of eggs, to get the mixture right.

  1/4 cup (60 ml) brown sugar

  When Rombauer and Becker say "brown sugar", they mean "firmly packed light brown sugar". I prefer to use Domino's brand "brownulated" granulated brown sugar.

  1/2 cup (120 ml) white sugar

  When Rombauer and Becker say "white sugar", they mean "standard granulated sugar."

  1/4 cup (60 ml) flour

  Use only enough flour so that the mixture is about as stiff as whipped cream or beaten egg whites. Do not exceed 1/3 cup (80 ml) of flour, because too much flour will make a giant bubble form under the upper surface of the pie. Avoid this "extra crust" by taking it easy with the flour.

  1/2 teaspoon (2 ml) salt

  2 teaspoons (10 ml) pumpkin pie spice.

  Pumpkin pie spice contains cinnamon, ginger, nutmeg, and allspice.

  1 teaspoon (5 ml) vanilla.

  1/2 teaspoon (2 ml) maple syrup flavoring

  Or replace some of the sugar with maple syrup.

• The mixture should be about as stiff as whipped cream or beaten egg whites.
  It should not be soupy or viscous (like honey).
  You can thicken the mixture by adding more sweet potatoes or small amounts of flour.
  You can thin the mixture by adding more evaporated milk or eggs.
• Pour the mixture into the pie shell.
• Bake 15 minutes at 425 degrees Fahrenheit (220 degrees Celsius).
• Reduce heat to 350 degrees Fahrenheit (175 degrees Celsius),
  and bake about 50 minutes longer or until an inserted knife comes out clean.
• I often serve the pie with:

  Ice cream

  The cheaper, airier brands tend to melt better than the premium, heavier brands.

Enjoy!