This grilled tuna steak is a quick-and-healthy dish to prepare. Yellowfin tuna is very high in the minerals selenium and phosphorus, and high in potassium. It is also very high in niacin (vitamin B3), B6 and B12, and a good source of vitamin D.
A word of caution tough: because of the methylmercury contamination of fish, it is recommended to limit the consumption of fresh tuna and other fish containing high levels of mercury to 170 grams (about 1 serving) a week. Shrimps, canned light tuna, salmon, pollock and catfish are lower in mercury, and can be consumed up to 340 grams (about 2 servings) a week.
I served the tuna steaks with a healthy root vegetables and French lentils mash, which is vitamin- and nutrient-packed. I adapted it from the new book of Yotam Ottolenghi “Plenty More” (2014: 230).
This quantities in the recipe here serve 2. It’s ready in 45 minutes or so (but only 10 minutes or so for the grilled tuna steak).
Ingredients for the tuna
- 2 yellowfin tuna steaks (about 170 g each), rinsed. If from frozen: defrosted, rinsed, and the excess water removed with kitchen towels.
- 2 teaspoons of olive oil
Ingredients for the mash
- 30 g of French lentils, picked and rinsed
- 1 small celeriac (about 75 g), peeled and diced
- 1 medium carrot (about 80 g), peeled and cut into chunks
- 1 medium sweet potato (about 200 g), peeled and diced
- ½ butternut squash (about 200 g), peeled and diced
- 1 tablespoon of unsalted butter, diced
- 1 tablespoon of maple syrup
- 1 teaspoon of ground cumin
Prepare the mash: Bring a small pan of water to the boil, and add the lentils. Turn down the heat and simmer covered for about 25 minutes, or until the lentils are just tender and no longer crunchy. Strain and set aside.
In the meantime, bring a medium pan half-full of water to the boil. Add the celeriac and carrot, and cook for about 10 minutes. Then add the sweet potato and butternut squash, and cook for 10-15 minutes more, or until all the vegetables are cooked.
While the sweet potato and butternut squash are cooking, brush each tuna steak on both sides with the olive oil (about ½ teaspoon of each side). Season with salt and pepper to taste. Set aside.
When all the vegetables are cooked, start to preheat a cast iron grill pan on the stove for grilling the tuna.
In the meantime, drain well the vegetables and mash them. Stir in the butter, maple syrup, cumin and cooked lentils. Season with salt and pepper to taste. Keep cover to keep warm.
When the grill pan is very hot, grill each side of the tuna steak for 2 to 2 ½ minutes.
And serve at once!