1 5/8 cups (228 g) all purpose gluten free flour (I like Better Batter here; click the link for full flour blend info)
¾ teaspoon xanthan gum (omit if your blend already contains it)
¼ cup (36 g) cornstarch (See Recipe Notes)
¼ teaspoon kosher salt
1 teaspoon baking soda
1/8 teaspoon wasabi powder (optional)
6 ounces semi-sweet chocolate disks or chips
8 tablespoons (112 g) unsalted butter, at room temperature
½ cup (120 g) mellow white miso paste
½ cup (100 g) granulated sugar
½ cup (109 g) packed light brown sugar
2 eggs (100 g, weighed out of shell), at room temperature
2 teaspoons pure vanilla extract
For the cornstarch
If you’re using a higher starch blend, like Cup4Cup, in place of cornstarch, use an equal amount of additional flour blend. If you can’t have corn, you can try using arrowroot or even potato starch in its place.
For the wasabi powder
You can use up to 1/2 teaspoon of wasabi powder, for more heat. You can also leave the ingredient out altogether. I like Eden brand.
Preheat your oven to 325°F. Line large baking sheets with unbleached parchment paper and set them aside.
In a medium-size bowl, place the flour, xanthan gum, cornstarch, salt, baking soda, and optional wasabi powder. Whisk the ingredients together, then add chocolate pieces, mix to combine, and set the bowl aside.
In the bowl of a stand mixer fitted with the paddle attachment or a large bowl with a hand mixer, place the butter butter, miso paste, granulated sugar, and brown sugar, and beat until very well-combined. Add the eggs and vanilla, and beat until smooth. Add the dry ingredients and chocolate pieces, and mix until just combined. The cookie dough will be thick, but soft and sticky.
Scoop the dough into portions about 1 1/2 tablespoons in volume, and place about 1 1/2 inches apart on the prepared baking sheets. With moistened fingers, pat down the dough into 1/2-inch thick disks and smooth any rough edges.
Place the baking sheets, one at a time, in the center of the preheated oven and bake until set and lightly golden brown all over and set in the center, about 14 minutes. Remove from the oven and allow to cool for at least 10 minutes on the baking sheet or until firm before transferring to a wire rack to cool completely.