Negitoro Maki ‡ Recipe

Rinse 2 cups short-grain sushi rice under cold water, swishing with your hand until the water runs clear (about 4–6 rinses). Drain.

Combine rinsed rice and 2.2 cups water in a rice cooker or heavy pot. Cook according to rice cooker instructions or bring to a boil, reduce to low, cover and simmer 12–14 minutes. Let rest, covered, 10 minutes.

While rice cooks, warm 4 tbs rice vinegar, 2 tbs sugar and 1 tsp fine sea salt in a small saucepan over low heat just until sugar and salt dissolve. Do not boil. Cool to near room temperature.

Transfer cooked rice to a large shallow wooden or plastic bowl. Gently fold the vinegar mixture into the rice with a wooden paddle or spatula using cutting and fanning motions to cool the rice and avoid crushing grains. Aim for glossy, slightly sticky rice. Cover with a damp towel while preparing fillings.

Ensure the bluefin tuna belly (otoro) is very fresh and sashimi-grade. Pat dry with paper towel. Finely chop or mince 8 oz of tuna belly on a clean board until it becomes a soft paste-like texture (traditional negitoro is scraped; chopping achieves similar result).

In a bowl, combine the chopped tuna with 1.5 tbs umeboshi paste. Mix gently to distribute the ume flavor without puréeing the fish. If desired, stir in 1 tsp sesame oil for a rounder aroma. Taste a small amount; the ume should add brightness and salt — adjust sparingly.

Fold in the finely sliced chives or negi (about 3 tbs) to the tuna mixture to create the negitoro. Keep chilled until assembly.

Place a bamboo mat on a work surface and cover it with plastic wrap to prevent sticking. Cut nori sheets in half crosswise to make 8 half-sheets (each full sheet yields two hosomaki rolls) if you want thinner rolls; or use full sheets for thicker rolls.

For hosomaki (thin rolls), halved nori

Place 1 half-sheet shiny side down on the mat. With wet hands, take approximately 3/4 cup seasoned rice and spread a thin, even layer across the nori leaving a 1 cm border at the top edge. Do not overpack.

For thicker rolls, full nori

Place a full nori sheet shiny side down. Use about 1 to 1 1/4 cups rice and spread leaving a 1 cm top border.

Place a 1/4 to 1/3 cup of the negitoro mixture in a thin line along the lower third of the rice-covered nori. Press the smoked trout roe (about 1/2 tsp to 1 tsp per roll) in a narrow stripe on top of the negitoro or scatter small pearls of roe along the line. The roe provides smoky briny pops; use sparingly so it doesn't overpower the tuna/ume balance.

Using the mat, lift the edge closest to you and roll away from you, tucking the filling in and pressing gently but firmly to form a cylinder. Roll until the open border seals; moisten the top border with a little water if needed to close.

With a very sharp, wet knife, slice each roll into 6–8 pieces (for half-sheet hosomaki make 6 pieces; for full-sheet make 8). Wipe the knife clean and wet between cuts to get clean edges.

Arrange negitoro maki on a platter. Garnish each piece with a small dab (about 1/8 tsp) of smoked trout roe on top of the cut face for additional visual appeal and smoky flavor, and sprinkle a few toasted sesame seeds if using.

Serve immediately with soy sauce and optional wasabi on the side. Consume promptly since raw fatty tuna is delicate — best within 30–60 minutes of assembly.

Leftovers: keep tightly covered in the refrigerator and consume within 24 hours; note texture and flavor will degrade.