Preheat your oven to 400°F (200°C). Wrap the Chioggia beets in aluminum foil, drizzle with olive oil and sea salt. Roast for 45-60 minutes until fork-tender. Cool, then peel and slice into strips.

In a mixing bowl, whisk together rice vinegar, tamari, sesame oil, and grated ginger. Toss the beet strips until well-coated. Marinate for at least 15 minutes.

Prepare short-grain white rice according to package instructions. Mix in sugar, a splash of rice vinegar, and a pinch of sea salt. Let it cool slightly.

On a bamboo mat, lay a nori sheet shiny side down. Spread sushi rice across the lower two-thirds of the nori, add marinated beets, cucumber, and avocado.

Roll the sushi tightly using the bamboo mat, then squeeze gently to secure. Set aside for slicing.

Slice the roll into bite-sized pieces with a sharp knife, cleaning the blade between cuts. Garnish with sesame seeds and serve with dipping sauces.