Mứt Gừng (Vietnamese Candied Ginger)

Fill a large bowl with cold water and add half of the lemon juice. Peel the ginger, removing any blemishes from the root and then place in the bowl of lemon water until all pieces have been peeled. Using a mandoline with its thinnest plate, slice the ginger roots. Place the ginger slices in the bowl of water until all have been cut.

Fill a large pot with water and the rest of the lemon juice. Transfer the ginger slices to the pot and bring to a boil. While the ginger is boiling, spray two cooling racks with nonstick spray and place them on cookie sheets that have been lined with parchment. Cook the ginger in the pot for 25 minutes, skimming off any impurities that may build up. Drain the slices in a colander and flush with cool tap water. Rinse the ginger 2 or 3 times and shake off excess water. Use paper towels to dry the ginger slices off well.

In a large pan over medium-low heat, add the ginger slices with sugar. Use chopsticks to coat the slices with sugar. Continue to stir as the sugar begins to melt and bubble. Stir in the vanilla extract and lemon zest. Continue cooking and stirring the ginger until the liquid has evaporated and the sugar has crystallized onto the slices. This process takes about 15–20 minutes.

Remove from heat and transfer the slices to the cooling sheets. Be sure to spread the slices into one even layer—flatten out any slices that may have folded over or curled up. Allow an hour for the slices to completely dry. Store in Ziploc bags or other airtight containers.