Special equipment: 12 mini tart molds
For the roasted peanut crumble crust: Position the rack in the middle of the oven and preheat to 350 degrees F. Mix the flour, butter, peanuts, sugar and salt in a food processor until crumbly. Press the mixture 1/3-inch-thick into 12 mini tart molds. Bake the tarts on deep baking sheets until golden, 15 to 20 minutes. Let cool.
For the goat cheese filling and assembly: Turn the oven temperature down to 325 degrees F. Combine the cream cheese, goat cheese, 1/4 cup of the sugar, the vanilla and egg yolks in a food processor. Mix, scrape the sides, and mix again until smooth. Whip the egg whites with the remaining sugar in a bowl until stiff peaks form. Delicately fold the meringue into the cheese mixture, and then spoon the batter into the cooled mini crusts. Pour hot water into the bottom of the deep baking sheet until it reaches halfway up the sides of the pie molds. Bake 20 minutes, and then remove the molds from the water and let cool. Remove the tarts from the molds and refrigerate 1 hour.