Vegan Ramen Broth

Cook onion, shallot, garlic cloves and ginger in a large cast-iron pan over high heat, turning occasionally, until the vegetables are lightly charred on all sides, 8 to 10 minutes. Transfer the vegetables to a large pot and add cabbage, carrot, scallions, kombu, mushrooms and water. Cover and bring to a boil over high heat. Reduce heat to maintain a simmer and cook, covered, for 1 hour.

Remove from heat, uncover and let stand, stirring occasionally, until the pot is cool to the touch, about 1½ hours. Refrigerate overnight.

Using tongs and a slotted spoon, remove most of the solids from the broth. Strain the remaining broth into a large saucepan. Bring to a simmer and serve hot.