Step 1

Bring cranberries, sugar, ginger, butter, and salt to a boil in a large saucepan over medium-high heat, stirring often to prevent scorching and help dissolve sugar. Continue to cook, stirring often, until cranberries burst, mixture is syrupy, and pot is visible when a wooden spoon is dragged across the bottom (mixture should be reduced to about 1¾ cups), 10–12 minutes. Remove from heat and stir in lemon zest. Chill until cold, at least 1 hour.

Step 2

Do Ahead: Filling can be made 3 days ahead. Transfer to a nonreactive container; cover and chill.

Step 3

Place a rack in middle of oven; preheat to 350°. Toast walnuts on a rimmed baking sheet, tossing once, until golden brown, 10–12 minutes. Let cool.

Step 4

Pulse walnuts, granulated sugar, lemon zest, cinnamon, salt, cloves, nutmeg, baking powder, and 2 cups flour in a food processor until nuts are finely ground. Add butter and pulse until largest pieces are pea-size. Add 1 egg and process in long pulses until dough forms a ball around the blade. Divide dough in half. Wrap one half in plastic, flattening into a ½"-thick disk. Press the remaining half into tart pan, working it across bottom and up sides with floured hands to create an even layer. Chill the dough in the pan and the wrapped dough until cold, at least 1 hour and up to 3 days.

Step 5

Scrape filling into crust and spread into an even layer.

Step 6

Unwrap remaining dough and roll out on a lightly floured sheet of parchment paper, dusting with more flour as needed to prevent sticking, to a ⅛"-thick round.

Step 7

Cut dough into 8 strips.

Step 8

Arrange strips over top of tart in a crosshatch pattern (this dough is delicate, so don’t fuss with strips too much once they’re on the tart). Pinch off excess dough and press strips into edges to adhere. Chill 15–20 minutes.

Step 9

Beat remaining egg in a small bowl and brush over crust.

Step 10

Bake tart until crust is golden brown around the edges and golden across surface and filling is bubbling, 45–55 minutes. Let cool.

Step 11

Just before serving, remove ring from pan and dust tart with powdered sugar.

Step 12

Do Ahead: Tart can be baked 1 day ahead. Store tightly wrapped at room temperature.