Heat a skillet over medium-high heat and add 1 teaspoon of toasted sesame oil. Sauté finely chopped zucchini and carrots for 3-4 minutes until soft.

In a large bowl, combine the cooked rice, sautéed vegetables, remaining sesame oil, and rice vinegar, mixing thoroughly.

Scoop 2 tablespoons of rice mixture, flatten it, add filling at the center, and mold into a compact ball.

Repeat until all components are used. Cover finished rice balls with a damp cloth to keep moist.

Serve fresh or wrap in plastic wrap and store in an airtight container for up to 3 days.