Recipe for 4 portions
1. Boil the sweet potatoes
In a small pot, bring enough salted water to a boil for the sweet potatoes. Peel the sweet potatoes, quarter them lengthways and then cut them into chunks. Add to the boiling water and cook for 10–15min. Tip: The potatoes are done when they come away easily from the knife when you test them.
2. Prepare the fish
Pat the fish dry and cut it into "tartare style" cubes of about 1cm squares. Fill the sesame seeds into a bowl and coat the fish cubes on all sides with the seeds. Slice the spring onions thinly on an angle and reserve some of the green part for garnishing. For the glazing sauce, mix the garlic and ginger paste with the sesame oil, the soy sauce and the spice mix.
3. Fry the fish
Heat up a large pan on medium-high heat and add 1Tbsp of olive oil. When the oil is hot, fry the tuna cubes for ca. 2min., shaking the pan to turn them regularly. Add the spring onion slices to the pan and fry for 1min. Then turn the heat to low and deglaze the pan with the sauce, reducing it for ca. 30sec.
4. Mash the potatoes
Reserve some of the cooking water in a cup, then drain the sweet potatoes into a sieve. Return to the pot and mash to a creamy mash, adding cooking water as needed. Tip: If you like, you can also add a little butter or oil. Season with a large pinch of salt.
5. Cut the avocados
Halve the avocados, remove the pit and score the flesh crosswise. Use a spoon to scoop the avocado cubes out of the skin. Zest and juice one lime and cut the other lime into wedges.
6. Marinate the avocado
Mix the avocado cubes with the lime zest and juice in a bowl. Season with a large pinch of salt. Spread the sweet potato mash onto plates and top it with the marinated avocado cubes, the fried tuna tartare and finally ½ of the seaweed caviar. Sprinkle with the reserved spring onion greens and serve with the lime wedges.