Add the liner to your Instant Pot, then add the oil and press the SAUTE button. Once the oil's hot (shimmery) add the garlic and ginger paste, stirring to incorporate. Let them saute for about 30 seconds.
Add the thinly sliced strips of chicken to the hot oil, and let them saute for 3-4 minutes- just until golden brown around the edges, and stirring occasionally.
Pour half of the water in, stirring to deglaze the bottom of the pot, and using the back of a sturdy wooden spoon scrape up and stuck on browned bits.
Add the lid to the pot, turning to close. Set the vent valve to the sealed position, and cook on HIGH pressure for 1 minute.
When done cooking, carefully open the vent valve avoiding the hot steam spray, and perform a quick release. Carefully open the lid, and hit the CANCEL button.
In a small bowl combine all of the sauce ingredients, including the remaining water. Whisk together until evenly combined and no lumps of cornstarch remain. Pour into the pot, and stir to evenly incorporate.
Hit the SAUTE button, but this time make sure it's on low. Add the broccoli florets, stirring to incorporate. Cook, simmering the sauce and stirring occasionally, just until the sauce has reached your desired thickness.
Press the CANCEL button to turn off the Instant Pot. Cover with the lid, and allow the chicken & broccoli to rest for 5 full minutes while the broccoli finishes steaming.
Serve over steamed white rice or cooked lo mein noodles and enjoy!