Ingredients:
2.5 poundsmixed tomatoes, cut into ¾” wedges, or halved if using small or cherry tomatoes
5 sprigsfresh thyme
1/4 cupextra-virgin olive oil
Sea salt and freshly ground black pepper
1 1/2 cupsall-purpose flour, plus more for fusting
1/2 cupwhole wheat flour
3/4 cup(1½ sticks) chilled unsalted butter, cut into pieces
1 tablespoonapple cider vinegar
1/3 cupice water
4 ouncesfirm cheese (such as Gruyere, cheddar, or Gouda), finely grated (about 1½ cups)
2 ouncesgrated Parmesan
3 garlic cloves, thinly sliced
1 large egg, beaten to blend
2 teaspoonsthyme leaves
Directions:
Place a rack in the center of the oven and heat to 300°F. Line a sheet tray with parchment paper. Arrange tomatoes and thyme sprigs on prepared sheet tray skin-side down; season with salt and pepper and drizzle with olive oil. Bake until deep red, juices have concentrated and the tomatoes have reduced in size and are dry on the surface, about 2 hours. Discard thyme and set aside until cool.
Pulse 1 ½ cups all-purpose flour, whole wheat flour and 1¼ tsp. sea salt in a food processor to combine. Add butter and pulse until mixture resembles coarse meal with a few pea-size pieces of butter remaining.
Transfer mixture to a large bowl; drizzle with vinegar and 1/3 cup ice water. Mix with a fork, adding more ice water by the tablespoonful as needed, just until a shaggy dough comes together. Turn out onto a work surface and lightly knead until no dry spots remain (be careful not to overwork). Pat into a disk and wrap in plastic. Chill at least 2 hours.
Unwrap dough and roll out on a lightly floured sheet of parchment paper to a 14″ round about ⅛” thick. Transfer on parchment to a baking sheet. Scatter both cheeses over dough, leaving a 1½” border. Arrange roasted tomatoes and garlic over cheese. Bring edges of dough up and over filling, overlapping as needed to create about a 1½” border; brush dough with egg. Sprinkle tomatoes with sea salt and pepper. Chill in freezer 10 minutes.
Bake galette at 400°F, rotating once, until crust is golden brown and cooked through, 55 to 65 minutes. Let cool slightly on baking sheet.