Rinse sushi rice under cold water until water runs clear. Combine rinsed rice with water in a medium saucepan, bring to a boil, cover, and simmer for 15 minutes. Remove from heat, let sit covered for 10 minutes.

Heat sesame oil in a skillet over medium-high heat, add sliced mushrooms, and sauté for 5-7 minutes until golden and tender. Season with salt and pepper, stir in miso paste and soy sauce, and set aside.

Add vegetable oil to the same skillet, increase heat to medium-high. Once hot, add cooked sushi rice, forming a flat layer, press down gently, and fry for 5-7 minutes until golden and crispy.

Spread the sautéed mushroom mixture over the fried rice, cook for an additional 2-3 minutes to meld flavors.

Remove from heat, garnish with chopped green onions and sesame seeds, add cilantro or parsley if desired, and serve warm.