Adding ginger and soy sauce to caramelized onions gives a bit of zingy punch and intrigue, creating a multidimensional meal that comes together in just one skillet. Covering the onions briefly during the beginning of the cooking process helps them break down more quickly—a baking sheet will work if you don’t have a lid!
- 3 Tbsp. extra-virgin olive oil, divided
- 2 medium onions, thinly sliced
- 1 1" piece ginger, peeled, sliced into matchsticks or finely chopped
- 1 medium russet potato, scrubbed, sliced into ¼"-thick rounds
- 2 5–6-oz. cod, pollock, halibut, or other flaky white fish or salmon fillets
- 2 scallions, trimmed, thinly sliced
- Furikake, shichimi togarashi, sesame seeds, mild red pepper flakes, or other fun sprinkly topping (for serving; optional)
Heat 2 Tbsp. oil in a large skillet over medium. Add onions, season with salt, and cover. Cook, uncovering and stirring occasionally, until onions are softened and just beginning to take on color, about 5 minutes. Uncover, add ginger, and cook, stirring occasionally, until onions are jammy and golden brown, 10–12 minutes. Stir in soy sauce. Transfer onion mixture to a plate and wipe out skillet.
Pour remaining 1 Tbsp. oil into same skillet and increase heat to medium-high. Add potatoes in a single layer and season with salt. Cook, turning halfway through, until golden brown, 10–12 minutes.
Spread onion mixture over potatoes, leaving a 1" border of potatoes without onion mixture. Season fish with salt and place on top of onion mixture. Cover and reduce heat to medium-low. Cook until fish is opaque throughout and easily flakes apart, 10–12 minutes. Serve topped with scallions and furikake (if using).