To your Instant Pot or pressure cooker, add 16 ounces of pasta along with 1 ½ cups of Italian dressing and 4 cups of vegetable broth.
Close the lid and set the valve to sealing.
Pressure cook on HIGH for 4 minutes. It may take 5-10 minutes for the Instant Pot to come to pressure before the 4 minutes begin.
Once the 4 minutes are up, press CANCEL and then let the pressure release naturally (meaning don't do anything) for 5 minutes.
After the 5 minute natural release, switch the valve to venting and manually release any remaining pressure until the floating pin drops.
Remove the lid and stir the pasta. There should be a small amount of broth/dressing left in the pot.
Place the cooked pasta into a very large bowl or other container, and put it in the fridge for about 1 hour or until it is cooled.
Once cool, remove from the fridge and add the chopped cucumber, the sliced tomatoes, and the fresh arugula.
Toss these all together until very well combined.
Taste the dish and season with salt and pepper to your liking.
If you consume dairy and would like to add cheese or anything extra, do so at the end.
Serve cool and enjoy!