Combine graham cracker crumbs, 1/4 cup sugar, and butter in a large bowl until the mixture has the consistency of wet sand. Press it tightly into a 9-inch pie plate, using a measuring cup to smooth the bottom and your fingers to smooth and pack the crumbs up the side of the pan. Place in the refrigerator to set while you prepare the filling.
In a medium saucepan, combine 2 cup heavy cream, peanut butter, molasses, and brown sugar. Cook over medium-high heat, whisking vigorously, until the mixture is smooth and starts to simmer.
Meanwhile, place the gelatin and water in a very small pan. Wait 1 minute and then gently heat over medium-low heat until the gelatin is completely dissolved. Add all of the gelatin into the peanut butter mixture, whisking to fully incorporate.
Pour the pie filling into the cooled crust. Wait for the filling to come to room temperature, then cover with foil and chill in the refrigerator for 5 hours or overnight.
For the praline topping, add the remaining 1/2 cup dark brown sugar and rum to a medium saucepan and bring to a rapid simmer over medium-high heat. Continue cooking, stirring occasionally, until the the mixture becomes thick and syrupy. Now add the walnuts and raisins and mix to coat everything in the caramel. Spread this mixture over the chilled pie and place back into the refrigerator for 5 to 10 minutes to set again.
Whip the remaining 1 tablespoon sugar and 1 cup heavy cream to soft peaks, and top the chilled pie with the whipped cream.
I was born in Peru to a Limeño father and a Texan mother. We moved to Miami when I was five, and I grew up in the "Kendall-suyo" neighborhood—often called the 5th province of the Inca Empire because of its large Peruvian population. I've been writing about food since I was 11 years old, and in 2016 I received a master's degree in Gastronomy from Boston University. A travel columnist at Food52, I'm currently based in Hollywood, Florida—another vibrant Peruvian community—where I am a writer, culinary tour guide, and consultant.