- 1 graham cracker crumb crust (Store bought or homemade)
- 6 cups watermelon (seeds are fine)
- 1⁄3 cup granulated sugar
- 2 tablespoons unflavored gelatin (aka, two envelopes)
- 1 tablespoon fresh lime juice or 1 tablespoon lemon juice
- 2 large egg whites, at room temperature
- 1 cup cold heavy cream or 1 cup whipping cream
- 1 cup confectioners' sugar, sifted
- confectioners' sugar, to dust
- whipped cream (homemade or store bought)
- Place a medium sized bowl and a set of beaters in the refrigerator to chill.
- Bake pie crust according to directions and let cool; Refrigerate until ready to use.
- Combine the watermelon and granulated sugar in a very large bowl; using a potato masher, mash until the mixture is quite liquid; set aside for 15 minutes.
- After 15 minutes, drain the mixture through a strainer, reserving almost 2 ¾ cups of the watermelon juice and then discard pulp and seeds.
- Put ¼ cup of the juice in a medium size bowl and sprinkle the gelatin over it; set aside for 3 to 4 minutes to dissolve.
- Heat ½ cup of the juice in a small saucepan over medium heat (or in the microwave) to a near boil; whisk the hot juice into the dissolved gelatin.
- Pour the remaining 2 cups watermelon juice into a large bowl an stir in the gelatin-watermelon juice mixture; stir in the lime juice; place in refrigerator.
- Using an electric mixer, beat the egg whites in a medium size bowl until stiff peaks form; set aside; clean and dry beaters;
- Using the chilled medium-size bowl and chilled beaters, beat the heavy cream with the mixer until it holds soft peaks; add the confectioners’ sugar and beat until smooth and stiff but not grainy; refrigerate.
- When the watermelon juice mixture starts to firm up, add about one-quarter of the whipped cream and beat with the electric mixer until smooth.
- Add the beaten egg whites and remaining whipped cream and gently fold them in with a large rubber spatula; if necessary, use a whisk-very briefly- to smooth the mixture and break up any large globs of whites or whipped cream;
- Pour the filling into the cooled pie shell; shake to settle; cover with loosely tented aluminum foil and refrigerate for at least 4 hours, preferably overnight.
- To serve, garnish each slice with a dusting of confections’ sugar, and then add a dollop of whipped cream, if desired.