1 cup pecans, toasted and cooled
2 cups ground graham crackers
1 tbs. plus 1 tsp. grated fresh ginger
2 tbs. dark-brown sugar
1/2 tsp. salt
1/2 tsp. ground cinnamon
6 tbs. butter, melted
4 large sweet potatoes
1/2 cup dark-brown sugar
2 tbs. bourbon
3/4 cup heavy cream
1 cup sugar
3 egg whites
1/8 tsp. salt
1/4 tsp. vanilla paste
Preheat the oven to 325 degrees. Grind the pecans in a food processor to a coarse powder. Add the graham-cracker crumbs, and grind with nuts until powdered. Add the ginger, dark-brown sugar, salt, and cinnamon, and process just to combine, then gradually pour in the melted butter until evenly distributed.
Press the crumb crust into a pie pan, shaping it evenly across the bottom of the pan and the sides. Bake the crust, flattening it with the back of a spoon every 10 minutes or so, until it is golden brown and stays firmly pressed in the pan (40 minutes to an hour). Set aside to cool.
Preheat the oven to 350 degrees. Roast the sweet potatoes until tender all the way through (about 1 hour), then cool to room temperature. Peel the sweet potatoes and purée in the food processor until smooth.
Reduce oven temperature to 325 degrees. Put 2 1/2 cups sweet-potato purée, the eggs, dark-brown sugar, and bourbon into a food processor, and process until combined, then stream in the cream until evenly incorporated. Pour into the cooled crust, and bake in the oven until the custard has set in the middle (about an hour). Cool to room temperature.
Combine the sugar and 1/3 cup water in a small saucepan, making sure there are no sugar crystals clinging to the sides of the pan. Place over medium heat, and cook until bubbles thicken and slow.
While the sugar is cooking, whisk the egg whites and salt in the bowl of a mixer to medium peaks.
When the syrup reaches 240 degrees on a candy thermometer, remove from the heat and stream it slowly down the side of the mixer bowl into the whites while whisking on high speed. Continue whisking until very stiff and just slightly warm. Add the vanilla paste, and mix just to combine. Spoon the meringue on top of the pie, making decorative swirls. Lightly brown the top of the meringue with a kitchen torch, and serve at room temperature.