Spray or grease the liner of the Instant Pot. (I use an olive oil spray or an avocado oil spray.)
Core and slice apples. You can peel your apples if you wish. It seems that peeling half of the apples helps create the best consistency.
Add sliced apples to the greased Instant Pot.
To the apples, add 1/2 teaspoon of cinnamon, and a pinch of salt.
In a measuring cup or bowl, combine apple juice, lemon juice, apple cider vinegar, and vanilla extract.
Pour half of the apple juice mixture over the apple and add the extra 2 tablespoons of water. Set aside the remaining liquid.
In a small bowl or a cup, mix arrowroot flour/cornstarch with 2 tablespoons or so of water.
Add arrowroot/cornstarch mixture to the apples and stir until apples are coated and cinnamon is well distributed.
In a large bowl, add rolled oats, flour, brown sugar, remaining cinnamon, nutmeg, cloves, and salt if using unsalted butter.
Add melted butter and stir until well combined.
Once oat topping is spread over the apples, gently pour the reserved apple juice mixture over the oat topping.
Close Instant Pot and set valve to sealing.
Press Manual and set for 1 minute. It will take between 7 to 10 minutes to come to pressure and then the countdown for 1 minute will start.
When cooking time is finished, do a quick steam release.
Transfer the crisp to another baking dish and let it sit and cool for ten minutes before serving.
OR if you would like a crisper topping, transfer the apple crisp into an oven-safe dish and broil it in the oven for 3 to 5 minutes to brown the topping.
Making apple crisp in an Instant Pot can be a bit tricky… and there is a risk of your apples getting too soft. The type of apples really affects how the crisp cooks. Some types of apples break down very quickly while others are drier and keep their shape. Small firm apples such as Granny Smith, Gala, or Ambrosia, work well.
Newer models of the Instant Pot can be more sensitive to triggering a "burn notice" if food sticks to the bottom of the pot while cooking. If you get a burn message, add a couple more tablespoons of water and turn the pot a quarter turn to move the spot where the heat is concentrating. You may also want to stir the crisp and scrape anything that is sticking from the bottom of the Instant Pot.