Step 1

Preheat the oven to 182 degrees C (360 F). Line a cookie sheet with parchment paper.

Step 2

Combine flour and baking soda in a small bowl. Stir to mix well.

Step 3

Add butter and sugar into a big bowl. Mix with a hand mixer on medium speed until combined and fully and a peak forms, after about 5 minutes. Add the egg, miso paste, and vanilla extract. Keep mixing until combined.

Step 4

Add the flour mixture. Mix with a spatula until barely combined.

Step 5

Add chocolate and fold into the cookie dough.

Step 6

Divide the dough into 12 to 18 portions by using a cookie scoop, and place onto the cookie sheet, at least 5-cm (2-inch) apart. Sprinkle with flaky sea salt.

Step 7

Bake for 12 minutes, or until the edges are golden but the centers are gooey. You might need to bake them in two batches.

Step 8

Transfer the cookie sheet onto kitchen counter and let cool for 15 minutes.

Step 9

The cookies taste the best while warm.