Step 1

Heat 3 Tbsp. vegetable oil in a medium Dutch oven or other heavy pot over medium. Cook 4 scallions, white and pale green parts only, thinly sliced on a diagonal, 6 garlic cloves, finely chopped, and one 1" piece ginger, peeled, finely chopped, stirring often, until fragrant and garlic is translucent, about 3 minutes. Add ⅓ cup white miso, 1 Tbsp. soy sauce, and 1½ cups water and stir to combine, breaking up any lumps. Stir in 1 Tbsp. unseasoned rice vinegar and 1 tsp. honey.

Step 2

Add 2 large Yukon Gold potatoes (about 1 lb.), peeled, halved lengthwise, sliced crosswise ¼" thick, to pot and bring to a boil. Add 3 medium Japanese or Chinese eggplants (about 1 lb.), quartered lengthwise, cut crosswise into 3"-long pieces, reduce heat, and simmer, stirring occasionally and adding up to ¼ cup more water if needed, until potatoes and eggplant are tender, 12–15 minutes. Remove from heat and add all but 1 Tbsp. thinly sliced dark green scallion parts of 4 scallions. Taste and season with kosher salt if needed.

Step 3

Transfer stew to a large shallow dish or bowl and top with crushed unsalted roasted peanuts and remaining 1 Tbsp. thinly sliced dark green scallion parts.