Add all Queso ingredients into a blender. Bring to high speed until smooth.
If you have a high-speed blender, like a Vitamix, just keep the blender running on high until the sauce gets steamy and thick, about 5 minutes. If using a regular blender, pour blended mixture into a saucepan, bring to a boil, and simmer until thick.
Set prepared Queso aside.
Heat a large stock pot or Dutch oven over medium heat. Add onions and saute until they turn translucent, adding a little bit of vegetable stock or water if they start to stick. Add garlic and cook another 30 seconds.
Add vegetable stock. Add dehydrated hash browns and stir. Bring to a boil and simmer 15 minutes (boil 7 minutes if using frozen or fresh hash browns).
Add broccoli, stir, cover and cook 7 minutes until broccoli is tender.
Add Queso and stir. Add salt and pepper for seasoning, if needed, and Worcestershire sauce.
If you'd like the soup a little thicker, remove 2 cups, blend until smooth, and return to soup.
Remove from heat and serve.
This is a great way to cycle through your emergency stock of dehydrated potatoes!