Place large saucepan on stovetop over high heat. Add 4 cups low-sodium chicken broth, 1 cup water, 1 1-inch-long piece fresh ginger, 2 cloves garlic, 1 tablespoon miso paste, 1 tablespoon sambal oelek, 2 tablespoons low-sodium soy sauce, 2 teaspoons sesame oil, and 1 dash rice wine vinegar. Stir well to incorporate ingredients, then bring mixture to boil.
Once mixture reaches rolling boil, immediately reduce heat under saucepan to medium-low. Simmer mixture 10 minutes, stirring occasionally. After 10 minutes, use slotted spoon to remove ginger and garlic pieces.
Add 2 blocks dried ramen noodles to saucepan and cook noodles in broth mixture until noodles are soft.
Once all noodles have softened, use slotted spoon to transfer noodles from saucepan to serving bowls, dividing noodles evenly between bowls.
Pour broth over noodles, dividing broth evenly between bowls.
If desired, top ramen with halves of 2 large soft-boiled eggs. Garnish with thinly sliced scallions, black sesame seeds, ½ sheet nori, and chopped chicken. Serve ramen immediately.