Key Lime Pie Recipe

Crust

1. Get ingredients:
   • 56 g (4 tbsp) butter (unsalted, any temperature)
   • 1 egg yolk (16 g) (large, room temperature)
   • 168 g (2 cups) graham crackers
   • 2 g (1/2 tsp) kosher salt
   • 25 g (1/8 cup) sugar (white, granulated)
   • 1 pie pan (9-inch diameter, not deep dish, preferably glass)
   • mixing bowl (medium)
2. Melt in the microwave, then set aside and let cool at room temperature:
   • 56 g (4 tbsp) butter
3. Set the oven to bake, 350° F (177° C). Ensure the oven rack is in the middle position.
4. Crush:
   • 168 g (2 cups) graham crackers
   • Use a food processor or put the crackers in a sealed plastic or silicone bag and crush the crackers with a rolling pin.
5. Add to large mixing bowl:
   • crushed graham crackers
   • 2 g (1/2 tsp) kosher salt
   • 25 g (1/8 cup) sugar
   • melted butter
   • 1 egg yolk (16 g)
6. Using a spatula or your hands, stir until the mixture is uniform and looks like wet sand. The mixture should hold together when squeezed.
7. Transfer the mixture to the pie pan.
8. Using a measuring cup, firmly press the mixture into the bottom and up the sides of the pie pan.
   • Optionally, use a sharp knife to even out the top edges.
9. Bake for 8-10 minutes (or until the top edge is lightly browned).

Filling

1. Get ingredients:
   • 5 egg yolks (large, about 75 g)
   • 6 limes
   • 300 ml (1 cup) condensed milk (sweetened)
   • 1 g (1/8 tsp) kosher salt
   • 4 g (1 tsp) vanilla extract (pure)
   • mixing bowl (large)
   • juicer
   • strainer (small)
   • whisk
   • zester
2. Clear some space in the fridge (for chilling the pie later).
3. Get a small bowl and an airtight container to store egg whites to use for the meringue later. Ensure both containers are clean and dry.
4. Separate 5 eggs. Ensure no egg yolks get into the egg whites.
   • Crack an egg over the small bowl.
   • Allow the egg white to pour into the small bowl while keeping the yolk in the egg shell.
   • Once the egg white is in the small bowl, add the egg yolk to a large mixing bowl.
   • Transfer the egg white to the airtight container to prevent yolk from the next egg accidentally getting into the clean egg white.
5. Store the airtight container with the egg whites in the fridge to use for the meringue later.
6. Wash 6 limes.
7. Set the oven to bake, 325° F (163° C). Ensure the oven rack is in the middle position.
8. Zest 3 limes to get 5 g (1 tbsp) lime zest.
9. Add to large mixing bowl with the egg yolks:
   • 5 g (1 tbsp) lime zest
10. Zest the remaining limes, but set aside the zest to use for decoration later.
11. Juice 6 limes to get 161 g (2/3 cups) lime juice.
12. Strain the juice into a small cup or bowl and set aside.
    • Discard the pulp.
13. Add to large mixing bowl:
    • 300 ml (1 cup) condensed milk
    • 4 g (1 tsp) vanilla extract
    • 1 g (1/8 tsp) kosher salt
    • 5 egg yolks (80 g)
14. Whisk until smooth (about 1 minute).
15. Add to large mixing bowl:
    • 161 g (2/3 cups) lime juice
16. Whisk until smooth (about 1 minute).
17. Pour the filling into the pie pan.
18. Bake for 15-20 minutes (or until the filling is set around the edges but still slightly loose in the centre).
    • When shaken, the filling should hold together as one piece, but with some movement.
    • There should be no browning.
19. Let cool at room temperature in the pie pan for 1 hour.
20. Chill the pie in the fridge for 4-24 hours.
21. An hour before making the meringue, remove the egg whites from the fridge to bring them to room temperature.

Italian meringue

1. Get ingredients:
   • 2 egg whites (68 g) (large, room temperature)
   • 1 g (1/4 tsp) cream of tartar (or lemon juice or white vinegar)
   • 2 g (1/4 tsp) salt
   • 100 g (1/2 cup) sugar (white, granulated)
   • 7 g (1/2 tbsp) vanilla extract (pure)
   • stand mixer
   • thermometer
   • saucepan (small, 1 litre)
2. If the eggs are not room temperature, place them in a bowl of warm water for a few minutes.
3. Ensure the stand mixer bowl and whisk attachment are clean and dry.
4. Attach the whisk to the stand mixer.
5. Add to stand mixer bowl:
   • 2 egg whites (68 g)
   • 1 g (1/4 tsp) cream of tartar (or lemon juice or white vinegar)
6. Mix on medium-high speed until soft peaks form (about 5 minutes).
7. Turn off the stand mixer. Set aside.
8. Add to saucepan:
   • 100 g (1/2 cup) sugar
   • 59 g (1/4 cup) water (any temperature)
9. Set heat to medium-high.
10. Let sit until it comes to a boil and reaches 240-245° F (115-118° C) (about 7 minutes).
    • Do not stir.
11. Set stand mixer to medium speed.
12. Add to stand mixer bowl:
    • 1 g (1/8 tsp) salt
13. Slowly pour the sugar mixture into the stand mixer bowl.
    • Pour between the side of the bowl and the whisk.
    • If the sugar hits the side of the bowl, the sugar will harden and won't incorporate into the mixture. If the sugar hits the whisk, it could spray out of the bowl.
14. Add to stand mixer bowl:
    • 7 g (1/2 tbsp) vanilla extract
15. Set stand mixer to high speed.
16. Mix on high speed until stiff peaks form and the bowl has cooled down (about 2-3 minutes).

Assembly

1. Get tools:
   • piping bag (large)
   • 1-cm star piping tip (eg. Wilton 1M)
2. Fit the piping bag with the piping tip,
3. Using a spatula, scoop the meringue into the piping bag.
4. Pipe dollops of meringue on top of the pie.
5. Sprinkle the remaining lime zest on top.