If using a bouillon cube, take a moment to crush that up as much as you can.
Add 4 cups of water to the Instant Pot, then stir in the bouillon cube.
Add 16 ounces of short pasta. Do not stir the pasta, but pat it down to make sure the water is touching all of it.
Add 2 tablespoons of vegan butter.
Close the lid. Set the valve to sealing and Pressure Cook on HIGH for 4 minutes.
Once the timer stops, natural release for 5 minutes, then quick release the remaining steam until the pin drops.
Remove the lid on the Instant Pot and stir the noodles.
Set the Instant Pot to 'Keep Warm.'
Add all of the spices, except for the cornstarch, as well as the almond milk and combine thoroughly.
In a small bowl whisk together 1 tablespoon of cornstarch with 1 tablespoon of water until no clumps remain. Then, add that to the Mac and cheese and stir.
Add 2 more tablespoons of vegan butter if you need more creaminess.
OPTIONAL: Add 1 tablespoon of vegan mayonnaise to the end just to add a bit more richness and creaminess.
Taste the Mac and cheese and see if you need to adjust any levels of spices or salt.
Serve in a bowl and garnish with chives if possible.