While biscuits are baking, heat oil in a medium skillet over medium heat.
Add chorizo to skillet, breaking up large pieces with a spatula.
Cook, stirring occasionally, until chorizo is browned and crisp, about 8-10 minutes. Using a slotted spoon, remove chorizo to a small bowl.
Keeping heat on medium, whisk flour into the drippings in the skillet.
Continuously whisk until roux is smooth and turning a light golden brown.
Gradually pour in milk, whisking until incorporated.
Reduce heat to medium-low and continue to whisk constantly, until gravy is thickened, 5-8 minutes.
Stir half the chorizo into the gravy and season with salt, pepper, and hot sauce.
While biscuits are still hot, spoon gravy over them. Top with avocado, scallions, radishes, cotija cheese, hot sauce, and cilantro. Sprinkle remaining chorizo on top, as well.