
Bring a large pot of water to a boil over high heat. Then add romaine and blanch briefly, about 20 seconds. Immediately transfer the lettuce to a bowl of iced water to stop the cooking process. Then place romaine in a colander to drain excess water.
Place a pan over medium heat and add some cooking oil to coat the bottom, about 1 tablespoon. Add the minced ginger and sauté for a minute until fragrant. Then add the white parts of scallions and garlic and sauté for another minute.
Add doubanjiang to the pan, then stir and cook until fragrant and the oil looks red. Add oyster sauce and soy sauce and give everything a stir.
Add water and sugar. Stir and bring everything to a simmer. Taste and adjust the seasonings to your liking. Stir in sesame oil and turn off the heat.
Arrange blanched lettuce on a serving plate. Drizzle the garlic sauce over the vegetables and serve right away.