sweet potato pie

glazed baby sweet potatoes ✢ kieffer lime marshmallow
sweet potato crumble

glazed sweet potatoes

150g peeled baby sweet potatoes, or mature sweet potatoes cut into .5" x 3.5" batons
30g unsalted butter, melted
30g maple syrup
10g dark rum
10 gratings of tonka bean on microplane 
pinch of salt

Pack sweet potatoes in a single layer in a vacuum bag. Combine the remaining ingredients in a small bowl and pour over sweet potatoes. Pull a vacuum on the filled bag and seal. Cook in an 82C/180F water bath for 25 minutes. Empty contents of bag into a saute pan and set over med-high heat. Cook, tossing frequently, until liquid has reduced to a glaze and coats the sweet potatoes. Keep warm until ready to assemble.

sweet potato crumble

100g grated sweet potato
8g butter
35g orange juice
35g water

Melt the butter in a saute pan set over medium high heat. Add the shredded sweet potato and toss to coat evenly with butter. Add the orange juice and water and bring to a simmer. Cover and cook for about 5 minutes or until the potato shreds are just tender. Uncover and raise the heat to high. Cook until all liquid is evaporated and the shreds begin to sizzle. Immediately remove pan from heat and transfer contents to a parchment-lined baking sheet. Carefully separate and spread the shreds out in a single layer, ensuring that there are no clumps. Bake the shreds in a 76C/170F oven for about 90 minutes, or until they are dry and crisp, tossing, separating, and re-spreading the shreds several times. Cool completely.

30g pecans
60g flour 
15g muscavado sugar
15g malted milk powder
2g microplaned gingerroot
1g salt
a pinch each of ground cinnamon, nutmeg, cloves, and allspice
45g unsalted butter, cut in small dice

Place the cooled, crisp sweet potato shreds and the pecans in food processor and process in short bursts until reduced to sandy consistency. Add the remaining ingredients except for the butter, and process just until blended. Sprinkle the diced butter over top and process in short bursts, stopping when mixture forms small clumps. Transfer the crumbled dough onto a baking sheet and shake the sheet to evenly distribute the crumbs. Bake at 325F for 15-20 minutes to set the crumbs. Keep warm in a low oven until ready to assemble.

kieffer lime marshmallow

170g sugar
 5g kieffer lime leaves, chopped
1g kieffer lime or persian lime zest
28g water
185g liquid glucose (or substitute corn syrup) 

Place sugar, lime leaves, and zest in food processor and process until lime leaves and zest are reduced to fine pieces. Transfer contents to a small saucepan and add water. Cover and place over low heat until sugar is melted and liquid. Remove from heat and allow syrup to infuse for 15 minutes. Strain mixture through fine sieve and return syrup to saucepan. Add glucose and heat mixture to 120C/248F (firm ball stage).

67g water
7g powdered gelatin
2g vanilla extract

While syrup is heating, place the water in the bowl of a stand mixer and sprinkle the gelatin over the top. Position the bowl to the mixer and fit with the whisk attachment. When the syrup reaches 115C/240F,  turn the mixer on low. When syrup reaches the firm ball stage, immediately remove from heat and begin to pour the syrup slowly down the inside surface of the mixer bowl, with the mixer still on low. When approximately 1/4 of the syrup is in the bowl, turn the mixer up to high speed and continue slowly pouring the syrup down the side of the bowl, being careful to not pour it onto the whisk. Scrape the remaining syrup that is clinging to the saucepan (heat briefly if it has begun to harden) and add to the bowl. Continue beating the syrup on high speed until it is white and fluffy and has tripled in volume, about 10 minutes. Beat in the vanilla.

60g confectioner's sugar
40g cornstarch

While the syrup is being whipped, combine the confectioner's sugar and cornstarch and place half of it in a sieve. Line a baking sheet with parchment and dust thickly with the mixture. Place the remaining mixture in the sieve so that it is ready to dust over the top of marshmallow.
If the marshmallow is to be piped, have a bowl of hot water ready, large enough to insert the mixer bowl, to keep the marshmallow fluid. As soon as the marshmallow is ready, Place the mixer bowl in the bowl of hot water to keep the gelatin from setting, and immediately transfer about 1 cup of mixture to a piping bag fitted with a 3/8" tip. Pipe elongated shapes that mimic the baby sweet potatoes onto the dusted baking sheet. Forming the tapers takes a little practice: start by piping a small amount onto the surface of the marshmallow in the bowl and pulling the piping bag away quickly to form the leading taper. Then begin forming the marshmallows by piping about 2.5" onto the dusted baking sheet and anchoring it with the tip of a small knife while slowly pulling the remaining length into a fine taper from the piping bag until it breaks off. Dust the tops with the additional confectioners sugar/cornstarch mixture and allow the mixture to cool and firm before rolling in mixture to coat all sides.
Alternately, the marshmallows can be formed by scraping the entire mass (while still warm) onto the dusted baking sheet and quickly spreading with a heated spatula to .5" thickness. Dust the top with the additional confectioners sugar/cornstarch mixture and allow the mixture to cool and firm before cutting into .5" x 3.5" batons with a heated knife.

To assemble: Spread a thin layer of the warm sweet potato crumble on a serving dish. Top with an alternating row of warm glazed sweet potatoes and marshmallow. Brulee the top of the marsnhmallows with a torch. Serve immediately.