Bring a large pot of water to a boil.
Add the cauliflower florets and cashews, and boil for 7 to 10 minutes, or until the cauliflower is fork-tender.
Once the cauliflower and cashews are ready, add them to a high-speed blender along with the water, nutritional yeast, jalapeño juice, sea salt, starch, and garlic powder. Blend on high for 2 minutes, or until completely smooth and creamy.
Transfer to a medium saucepan. Heat over medium-low for 3 to 5 minutes, or until the sauce begins to thicken, whisking constantly.
Stir in the green chilis. Taste and season with more salt and/or pickled jalapeño juice, if desired. If you'd like to up the kick, stir in a few dashes of cayenne pepper, too.
Serve warm with plenty of tortilla chips for dipping.