Preheat oven to 350 degrees. In a large mixing bowl, whisk together flour, 3/4 cup sugar, baking powder, zest, and salt. Stir in almonds and ginger.
In a small bowl, whisk together eggs and vanilla; stir into flour mixture. (Dough will appear very dry but will come together when kneaded.)
Transfer dough to a lightly floured work surface; knead until smooth. Divide dough in half; shape into two logs, each about 1 inch high and 3 inches wide. Place on a parchment lined baking sheet; sprinkle with remaining sugar.
Bake until logs are puffed and outside is firm (the tops may crack), about 30 minutes. Transfer to a wire rack to cool completely, about 2 hours.
Using a serrated knife, thinly slice the logs crosswise,1/4 inch thick. Lay slices on two parchment-lined baking sheets. Bake until crisp and lightly golden, rotating pans and turning biscotti over halfway through, 20 minutes total. Cool completely before serving or storing.