Wash the apples really well. 

Core and chop apples into one inch cubes. No peeling is necessary.

Add the chopped apples to your Instant Pot. Pour in 1/2 cup of water and add the cinnamon sticks.

Close the lid and make sure the valve is pointed to "sealing". Press the "pressure cook" or "manual" button, set to high pressure for 30 minutes.

Once the pressure cooking portion is done, allow the apples to release naturally for 20 minutes, and then move the valve to "venting" to release the remaining steam.

Open the lid and remove the cinnamon sticks. 

Using an immersion blender, blend the apples (skins and all) until smooth. You can also ladle the apples into a blender or food processor to blend. Be careful! The mixture is hot.

Set your Instant Pot to the "saute" function and make sure it's set it to the "less" temperature setting. 

Add one cup of sugar and 2 tablespoons of lemon juice to the apples and stir.

Simmer the apples for 3-4 hours until the mixture is thick, and has reduced to 1/3 of its original volume. Stir every half hour while the mixture is cooking, to prevent burning.

You'll know the butter is done when it's thick and deep brown in color. Your spoon should leave drag marks when stirring, the simmering bubbles will start to slow down, and the butter will start to making popping sounds. 

When the apple butter looks done, give it a taste and add another tablespoon of lemon juice if you desire.

Press “cancel" to turn off the Instant Pot.

Ladle the apple butter into clean airtight containers and allow the butter to cool completely before storing in the fridge or freezer.