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Magic Key Lime Pie

Magic Key Lime Pie 8.000

Goran Kosanovic for The Washington Post

Book Report Jul 25, 2017

Key limes have a bracing acidity and take a lot of time to prep (when you can find them); by making your own sweetened condensed milk for this recipe, though, you can use regular limes and still achieve that perfect balance of flavors for the pie.

Homemade sweetened condensed milk traditionally requires ultra-low heat and up to 6 hours of constant stirring. Pastry chef Stella Parks adds a splash of heavy cream to prevent scorching and cranks up the heat so it’s done in about 45 minutes.

Make Ahead: The sweetened condensed milk can be refrigerated for up to 1 month. The pie, minus its topping, needs to be refrigerated for at least 4 hours and up to 3 days.

8 - 12

When you scale a recipe, keep in mind that cooking times and temperatures, pan sizes and seasonings may be affected, so adjust accordingly. Also, amounts listed in the directions will not reflect the changes made to ingredient amounts.

Tested size: 8-12 servings; makes one 9-inch pie

  • For the sweetened condensed milk
  • 4 cups milk (any fat percentage will do)
  • 3/4 cup heavy cream
  • 1 cup sugar
  • 1/8 teaspoon kosher salt
  • For the pie
  • 1/2 cup (5 ounces) egg yolks (from about 8 large eggs)
  • 2 tablespoons finely grated lime zest (no pith), plus 3/4 cup (6 ounces) juice (from 6 to 9 limes; see headnote)
  • 1 homemade or store-bought graham cracker crust (9 inches)
  • For the topping
  • 1/4 cup (2 ounces) sugar
  • Pinch kosher salt
  • 3/4 cup (6 ounces) heavy cream


For the sweetened condensed milk: Combine the milk, heavy cream, sugar and salt in a 5-quart pot over medium heat; cook, stirring occasionally with a heat-resistant spatula to help the sugar dissolve, about 12 minutes.

Continue cooking for an additional 30 minutes, scraping continuously to prevent a milky buildup from forming around the sides. Once the thickened milk-syrup suddenly begins to foam, it’s almost done. Keep cooking until the foam subsides and the dairy has condensed to exactly 2 cups. Pour into an airtight container, seal to prevent evaporation and refrigerate up to 1 month. To mimic the consistency of canned milk, bring to room temperature before using. You’ll need all of it for this recipe.

For the pie: Whisk together the egg yolks, lime zest, juice and the 2 cups of sweetened condensed milk in a 3-quart pot. Cook over medium-low heat, whisking gently to form a custard that is steaming hot, about 5 minutes. Increase the heat to medium; cook until the custard begins to bubble, about 5 minutes more (it won’t seem terribly thick).

Pour into the prepared crust and refrigerate uncovered until cold and firm, at least 4 hours. (Covered loosely in plastic at this point, the pie can be refrigerated for up to 24 hours.)

For the topping: Combine the sugar, salt and cream in the bowl of a stand mixer fitted with the balloon-whisk attachment. Beat on medium-low speed for a minute to dissolve the sugar, then increase the speed to medium-high; beat until the cream is thick and forms stiff peaks, about 5 minutes. Transfer to a pastry bag fitted with a large tip; pipe decoratively around the edges of the pie.

Wipe the serving knife clean between cuts.

Recipe Source

Adapted from “BraveTart: Iconic American Desserts,” by Stella Parks (W.W. Norton, August, 2017).

Tested by Jane Black .

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Nutritional Facts

Calories per serving (based on 12, without the topping): 270

% Daily Values*

Total Fat: 14g 22%

Saturated Fat: 7g 35%

Cholesterol: 155mg 52%

Sodium: 100mg 4%

Total Carbohydrates: 30g 10%

Dietary Fiber: 0g 0%

Sugar: 21g

Protein: 6g

*Percent Daily Value based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

Total Fat: Less than 65g

Saturated Fat: Less than 20g

Cholesterol: Less than 300mg

Sodium: Less than 2,400mg

Total Carbohydrates: 300g

Dietary Fiber: 25g

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