Kamo Nanban Soba From 'Japanese Soul Cooking'

Ingredients (10)

• 6 cups dashi
• 3/4 cup kaeshi
• 6 tablespoons mirin
• 2 duck breasts (about 1 1/2 pounds total)
• Salt
• 2 negi, white parts only, sliced into 1 1/2-inch pieces
• 4 servings soba (400 grams)
• 1/4 cup thinly sliced negi or scallion
• 4 teaspoons wasabi
• Shichimi togarashi