Swordfish Gratin
メカジキのグラタン
By Aoi, licensed nutritionist · From a Japanese preschool lunch menu
This is a gratin without the usual white sauce: sautéed swordfish and sweet onion form the base, a layer of mashed potato flavored with mayonnaise and a little curry powder goes on top, and it all bakes under a golden crust of panko and Parmesan. Swordfish is a favorite for children's lunches in Japan because it is meaty, mild, and has no small bones to pick out, so even little ones can eat it with confidence. The gentle curry flavor and crunchy topping make it easy to get fish eaters and fish skeptics alike to clean their plates.
Added. Open the recipe helper (bottom right) → ☰ Menu → 🛒 Shopping list to see the ingredients for your family size.
Printing uses the number of adults and children set under Ingredients, so set those first.

Ingredients
Amounts for 1 child (1 serving). An adult counts as 2 servings.
One serving here is 1.5× the portion served to a child in a Japanese preschool, sized for Western appetites. An adult counts as two servings. Tap an ingredient to check it off.
Ingredients
- 45 gswordfish
- 30 gonion
- 52.5 gpotato
Seasonings
- 0.1 gsalt
- 1.5 gvegetable oil
- 12 gegg-free mayonnaise (Mayodore)A Japanese egg-free mayonnaise-style dressing. Substitute: Any egg-free or vegan mayonnaise.
- 0.2 gsalt (to finish)
- 0.1 gcurry powder
- 1.5 gpanko
- 1.4 ggrated Parmesan cheese
- 0.1 gdried parsley
About the Japanese ingredients in this recipe
- egg-free mayonnaise (Mayodore) (マヨドレ)
- A Japanese egg-free mayonnaise-style dressing. Substitute: Any egg-free or vegan mayonnaise.
Directions
- 1
Cut the swordfish into 2 cm cubes and sprinkle with salt to season. Thinly slice the onion, then cut the slices in half.
- 2
Heat the oil in a pot and sauté the onion well. Once it has softened, add the swordfish and continue to sauté.
- 3
Boil the potato and mash it, then mix in the egg-free mayonnaise (Mayodore), the salt to finish, and the curry powder.
- 4
Line a baking sheet with parchment paper, spread the sautéed swordfish and onion evenly over it, and top with the mashed potato mixture.
- 5
Combine the panko and grated Parmesan cheese, sprinkle over the top, and bake in an oven preheated to 200°C (400°F) for about 15 minutes.
- 6
Once baked, sprinkle with dried parsley.
Nutrition
| Per | 1 serving | 1 adult serving | Your total |
|---|---|---|---|
| Energy | 195 kcal | 390 kcal | 195 kcal |
| Protein | 10.6 g | 21.3 g | 10.6 g |
| Fat | 12.5 g | 24.9 g | 12.5 g |
| Carbohydrates | 13.7 g | 27.3 g | 13.7 g |
| Fiber | 5.4 g | 10.8 g | 5.4 g |
| Salt equivalent | 0.8 g | 1.5 g | 0.8 g |
| Calcium | 27 mg | 54 mg | 27 mg |
| Iron | 0.6 mg | 1.2 mg | 0.6 mg |
| Potassium | 468 mg | 936 mg | 468 mg |
| Energy | Protein | Fat | Carbs | Fiber | Salt equiv. | Calcium | Iron | Potassium | |
|---|---|---|---|---|---|---|---|---|---|
| 1 serving | 195 kcal | 10.6 g | 12.5 g | 13.7 g | 5.4 g | 0.8 g | 27 mg | 0.6 mg | 468 mg |
| 1 adult serving | 390 kcal | 21.3 g | 24.9 g | 27.3 g | 10.8 g | 1.5 g | 54 mg | 1.2 mg | 936 mg |
Values are per serving (1.5× the Japanese preschool portion); an adult serving is double. They were calculated by a licensed Japanese nutritionist using the Standard Tables of Food Composition in Japan. "Salt equivalent" is sodium × 2.54, the standard Japanese measure. Allergen flags cover egg, milk and wheat only and come from the nutritionist's records. Soy sauce and miso are made with wheat but are usually allowed on Japanese wheat-free school menus, so check with your doctor.





