Cut the bottom part of the lettuce and separate the leaves. Wash in running water and drain in a colander to dry.
Fill a pot with water and put some cooking oil, salt and baking soda. Heat the water but do not let it boil.
Put the lettuce and blanch for 2 minutes. Then remove from pot and set aside.
In a bowl, combine water, cornstarch, oyster sauce, soy sauce, sugar and black pepper. Stir until the sugar is dissoved.
Heat cooking oil in a pan and sauté the ground pork. Stir until the color turns to white. Cover and simmer in low heat until the liquid evaporates and the pork renders some fat.
Set the pork aside and add garlic and sauté. Add minced carrot and minced bell pepper and stir for 2 minutes.
Add the cornstarch mixture and stir until the sauce is thick.
Arrange the lettuce in a platter and pour the meat sauce. Serve hot and enjoy!