Pre-heat waffle iron (over medium-high if it has temperature settings.) Spray both sides with non-stick cooking spray or brush with melted butter.

In a medium bowl, whisk together eggs and milk. Stir in potatoes, cheese, green onions and season with ½ teaspoon salt and ¼ teaspoon pepper.

Depending on the size of your waffle iron, scoop a layer of the potato mixture onto the surface. Amount could vary from 1/4 cup to 1 cup, depending on if you have a small Dash-type waffle maker, or a larger one. Spread to about ½ inch from the edges and close the waffle iron. Cook for about 5 minutes, checking every few minutes to avoid burning. When the entire waffle is golden brown in color, carefully remove from the waffle iron with a fork or tongs. I have the small Dash waffle maker, and I usually (gently and carefully) turn each waffle over towards the end to be sure both sides get nicely browned.)

Meanwhile, in a medium skillet, heat the oil over medium heat. Add the chorizo, stirring occasionally and breaking up with a spatula, until the chorizo is browned, about 10 minutes.

Remove from skillet with a slotted spoon to a paper towel lined plate to drain the grease off, but leave the drippings in the skillet.

With the heat still on medium, whisk in the flour and cook, whisking constantly, until roux is very smooth and starting to turn a light golden brown, about 5 minutes. Gradually stir in the milk, whisking constantly until incorporated. Reduce heat to medium-low and cook gravy, whisking constantly, until thickened, 5–8 minutes. Stir chorizo into gravy; season with salt, pepper, and hot sauce.

When waffles and gravy are both done, plate waffles and spoon gravy over the top. Top with shredded cheddar, sour cream, and chopped green onions, if desired.