Tuna Steak with Sweet Potato and Samphire

24 Jan, 2021
Salsify Pasta with Creamy Leek Sauce

Such a Great Combination!

Pan-fried tuna steak with mashed sweet potato and samphire are a very delicious combination. The perfect harmony of flavors and colors will impress your family and guests. It can be made in a very short time. This dish is gluten free. It is dairy free if you substitute butter with coconut oil.

Pan-fried Marinated Tuna Steak

Tuna is mainly sold as steaks. Tuna, like any other steaks, can be served cooked or rare. Up to you. I think the most delicious way is when it has a cooked bark from the outside and raw in the center.

The marinade adds flavor to the surface of the tuna steak but does not make it juicier. I use coconut aminos and sesame oil in this marinade. It is perfect substitute of soy sauce and gives a very nice sweet and salty flavor to tuna steak. We avoid soy in paleo diet.

Tuna can dry out very quickly. Cook on high heat in frying pan for 1-1.5 minutes each side. Then take it off the stove. Cover with foil and rest for a couple of minutes before serving.


Always pay attention to the tuna steak while frying, it can dry out very quickly. Buy thicker tuna steaks.

Flavored Mashed Sweet Potato

I add crushed garlic, grated ginger, ground nutmeg, butter, salt and pepper to the mashed sweet potato. This flavor combination goes very well with tuna steak. Tuna has a fairly robust flavor, therefore you can easily add herbs, spices to side dishes. Do not worry, they will not suppress the flavor of this fish.


Samphire (called as Green Salt and Sea Asparagus also) is a plant of green leaves with scale shape. It grows spontaneously in salty environments. This plant stores salt, which gives it a high nutritional value. It is rich in Vitamin C, A, complex B vitamins, Omega-3 oils. And a good source of minerals especially iodine, calcium and iron.

Samphire has such a distinctive crunchy texture and salty taste. It doesn’t need additional flavoring. Samphire goes very well with fish and seafood.

Rinse the samphire thoroughly and trim off any tough ends before use. I do not like to cook it in boiling water. I like it to stay crispy, so I just cook it in hot butter with a bit of lime juice for 2 minutes.

Salsify Pasta

Tuna Steak with Sweet Potato and Samphire

Prep Time15 mins
Cook Time25 mins
Marinating Time1 hr
Total Time1 hr 40 mins
Servings: 2
Author: Andrea


For the tuna

  • 2 slices tuna 200 gram each
  • 4 tbsp coconut aminos
  • 4 tbsp sesame oil
  • 1 tbsp olive oil
  • Salt and pepper

For the mashed sweet potato

  • 400 gram sweet potato cut into cubes
  • 1 clove garlic crushed
  • 1 tsp ginger grated
  • ½ tsp nutmeg ground
  • 1 tbsp grass fed butter
  • ¾ tsp salt
  • ¼ tsp pepper freshly ground
  • Salt and pepper

For the samphire

  • 100 gram samphire
  • 1 tbsp butter
  • 1 tbsp lime juice
  • 2 tsp sesame seeds roasted

For decoration

  • 4 slices beetroot chips optional


  • Marinate the tuna. Mix coconut aminos and sesame oil in a small bowl. Season tuna slices with few pinches of salt and pepper. Put tuna into ziplock bag and pour the coconut aminos mixture in it too. Lock the bag and set aside for 1 hour.
  • Make mashed sweet potato. Cook sweet potato cubes in salty water for 10 minutes from the first boiling, until soft.
  • Drain cooked sweet potato thoroughly. Mash it. Add crushed garlic, grated ginger, ground nutmeg, butter, salt and pepper. Mix them with kitchen spoon. Taste it and season more if necessary. Set aside.
  • Rinse the samphire thoroughly and trim off any tough ends. Heat butter in a frying pan. Put samphire and lime juice in it and cook for 2-3 minutes. Switch off the heat and add sesame seeds. Samphire basically salty therefore I do not add more salt. Set aside.
  • Make beetroot decoration. This step is optional. Put 4 slices of beetroot into hot oil and fry for 2-3 minutes, until they are bubbling but not burning, their color still red. Put them on kitchen paper.
  • Fry the tuna. Take the fish slices out of the ziplockbag and wipe dry with a kitchen paper. Brush the tuna steaks lightly with oil, and season with few pinches of salt and pepper. Heat a frying pan. Cook the tuna for 1-1.5 minutes then turn and cook the other side for 1-1.5 minutes also. (Cooking time depends on the thickness and the temperature of the slices.) When the slices have lighter lines on their bottom and the top and they are still pink in the middle, take the pan off the stove. It will keep cooking for a short while when taken off the heat. Cover with folie and rest for a couple of minutes before serving.
  • Heat mashed sweet potato and samphire.
  • Place mashed potato and samphire on a plate. Then place the tuna to the top. Enjoy!