If using frozen masago, thaw in refrigerator overnight or under cold running water until just pliable. Gently blot with paper towels to remove excess moisture; do not press or mash the eggs.

Make seasoning mixture

In a small bowl, whisk together the Japanese mayonnaise, soy sauce, mirin, sesame oil, and lime juice until smooth and emulsified.

Combine with masago

Place the drained masago in a medium bowl. Add the mayonnaise mixture and fold gently with a rubber spatula until the roe is evenly coated. Take care to fold; avoid vigorous stirring that will break the tiny eggs.

Add aromatics and finish

Fold in the finely chopped scallion and toasted sesame seeds. Taste and, if needed, season with up to 1/4 tsp kosher salt or a pinch more soy sauce. If you want a spicy kick, add the shichimi togarashi or a small pinch of cayenne and mix gently.

Chill briefly

Cover and refrigerate the seasoned masago for at least 15–30 minutes to allow flavors to meld. Do not store for more than 2 days prepared; keep refrigerated and use within 48 hours for best texture.

Serving Suggestions

Sushi rice bowls: Spoon seasoned masago over warm sushi rice (about 1/2 cup rice per serving). Top with avocado slices, cucumber, and a few nori strips. Garnish with microgreens or shiso.

Nigiri or gunkan: For gunkan-style, wrap a strip of nori around a small oval of rice to form a cup and fill with masago (about 1–2 tbs per piece). For nigiri, lightly press a small dab of masago onto a rice pillow and finish with a sliver of nori.

As a condiment: Serve in a small bowl alongside grilled fish, seared scallops, or as a topping for tempura-topped bowls. Bring to room temperature for 10 minutes before serving for best flavor.