Instructions

1. Arrange a rack in the middle of the oven and heat the oven to 175°F. Line a baking sheet with parchment paper.
2. Place 2 1/2 tablespoons miso paste and 1 tablespoon nanami chili paste in a small bowl and stir to combine. Transfer it onto the parchment and spread into a paper-thin layer. Bake until the paste is dry and slightly cracks when bent, about 1 hour 30 minutes. If it still feels gummy, continue baking until dry, 15 to 20 minutes more.
3. Meanwhile, heat a large nonstick skillet over low heat. Add 1 nori sheet (cut it up into smaller pieces if needed to fit) and toast until crisp but not burnt, about 1 minute per side. Transfer to a plate.
4. Add 1/4 cup white sesame seeds to the pan and toast tuntil fragrant, 3 to 5 minutes. Add 1 cup bonito flakes, 1 1/2 teaspoons soy sauce, 1 1/2 teaspoons soy sauce mirin, 1/2 teaspoon garlic powder, and 1/2 teaspoon granulated sugar. Stir constantly, breaking up bigger chunks, until the seeds turn golden brown, 10 to 12 minutes.
5. Transfer to a small bowl and set aside to cool for 10 minutes. Use your fingers to break up any large pieces of the bonito, then crumble the nori with your fingers into tiny flakes over the bonito mixture.
6. Remove the dried miso paste from the parchment. Break it up into pieces and place in a food processor fitted with the blade attachment or a blender. Process it into a fine powder. Transfer to the bowl with the bonito mixture and mix well to combine.
7. Transfer to an airtight container and store at room temperature for up to 3 weeks. A humid environment might cause it to clump — just shake it or refluff it with a fork to break it into tiny bits again.