Mince chile, garlic, scallion (white part only), and half of ginger. In a pan over medium-high heat, add grapeseed oil and minced ingredients, and sauté until fragrant and translucent. Add doenjang and soy sauce, stirring to combine; cook for 1 minute. Finally, add sugar, gochugaru, and sesame oil. Set aside
Butterfly the fish. Slice the other half of the ginger thinly and place on the flesh of the fish. Steam for 5 minutes.
Place sautéed aromatic mixture on top of the fish and steam for an additional 5-10 minutes until fully cooked.
Serve hot with steamed rice and garnish with sliced scallion greens.