Congee, a Chinese dim sum staple, is a simple and hearty savory rice porridge simmered with aromatics and often served with seasonal vegetables and meat. Congee can be made with many types of grains, but we like quick cooking jasmine for its soft texture that easily breaks down into a porridge.
Combine 4 cups chicken broth, the rice, ginger, white and light green parts of the leek and 1/2 teaspoon salt in a 6-quart Instant Pot. Put on and lock the lid, making sure the steam valve is in the sealing position. Set the pot to pressure-cook on high for 20 minutes.
Meanwhile, heat the vegetable oil in a large skillet over medium-high heat. Add the dark green parts of the leek and cook until they begin to soften, about 3 minutes. Add the mushrooms and 1/2 teaspoon salt and cook until the mushrooms are browned and the leeks are tender, about 5 minutes. Remove from the heat. Warm the remaining 3 cups chicken broth in the microwave.
When the time is up on the Instant Pot, carefully turn the steam valve to the venting position and let the steam release. Carefully unlock and remove the lid. Stir in 2 cups warm chicken broth. Set the Instant Pot to sauté on normal and cook, stirring constantly, until the mixture has thickened to a porridge, 5 to 7 minutes. If the mixture thickens too much, stir in some of the remaining chicken broth. Season with salt, if needed.
Divide the congee among bowls. Top with the shredded chicken, mushroom-leek mixture and soy sauce.