In a small bowl, whisk tamari, sugar, sesame oil, and pepper to combine.
Heat a wok or large skillet over high heat with a little oil.
Separately sauté the shrimp until opaque and pink, the mushrooms until browned, and the kimchi until dry. Add oil as needed between batches.
Coat rice with 2 tablespoons of oil then add to the wok. Cook until the rice starts to crackle and brown, about 3-5 minutes.
Make a well in the rice and add the beaten egg and cook through. Stir in tamari, sugar, sesame oil, and black pepper.
Fold in cooked ingredients with peas and heat through. Season to taste with reserved kimchi liquid, and additional tamari. Garnish with chopped cilantro or sliced green onion and serve promptly.
