Preparation

• Position a rack in the center of the oven and heat the oven to 375°F. Butter a 8-1/2 x 4-1/2-inch metal loaf pan and dust with flour; tap out any excess.

  Using the large grating disk on a food processor, pass the zucchini vertically through the feed tube to grate. (If the zucchini is too wide to fit, slice in half lengthwise.) Discard any remaining ungrated portions wedged on top of the disk. Transfer the grated zucchini to a colander or sieve set over a bowl. Sprinkle 1 Tbs. of the sugar over the grated zucchini and toss to distribute. Sprinkle another 1 Tbs. sugar over the zucchini and toss again. Set aside for 20 minutes.

  In a small saucepan, melt the butter over medium-low heat. Pour the butter into a medium bowl and let cool slightly, 5 to 10 minutes. Whisk the remaining 3/4 cup sugar, coffee, yogurt or buttermilk, and eggs into the butter.

  In a large bowl, combine the flour, chocolate, walnuts, baking powder, baking soda, salt, and cinnamon.

  Squeeze the zucchini by the fistful to thoroughly wring out excess liquid. Add the zucchini to the wet ingredients and stir to combine. Pour over the flour mixture and, using a large wooden spoon, stir until just blended.

  Spoon the batter into the prepared pan, spreading it evenly with a rubber spatula. Bake until a toothpick inserted in the center comes out clean, about 1 hour. Let cool on a wire rack for 10 minutes. Loosen the edges with a knife and release the bread, turning it upright onto the rack until completely cooled.