01 -
In a large bowl, whisk together the flour and salt. Add the butter and use your fingertips to work it into the flour mixture until the pieces are about the size of peas. If the butter becomes too soft, refrigerate the bowl for 5 minutes.
02 -
Drizzle in the apple cider vinegar and ice water, using a fork to combine them with the dry ingredients until a shaggy dough forms. Knead lightly to form a dough ball, then shape into a disk, wrap tightly in plastic wrap, and chill for a minimum of 2 hours.
03 -
Preheat the oven to 200°C (400°F). Sprinkle the tomato slices with salt and place them on a paper-towel-lined plate to drain excess moisture. Cook the bacon in a medium skillet over medium heat until crisp, 8–10 minutes. Transfer to a paper-towel-lined plate and cool before breaking into bite-size pieces.
04 -
Roll the dough on a lightly floured parchment paper into a 14-inch diameter circle, ⅛ inch thick. Arrange the tomato slices and bacon irregularly on the dough, leaving a 1½-inch border. Fold the edges of the dough over the filling, brush with egg wash, and sprinkle with salt and pepper. Chill for 10 minutes.
05 -
Bake the galette on a baking sheet until the crust is deeply golden and cooked through, about 50–60 minutes. Cool slightly, then transfer to a serving platter. Top with arugula, drizzle with olive oil, and garnish with flaky salt before slicing and serving.