cook chorizo in oil in a pot over medium-high heat, stirring often, until browned, about 5 minutes. transfer chorizo to a paper towel with a slotted spoon

add onion to fat in pot & saute until softened, 3 to 5 minutes. stir in garlic, chile flakes, & pepper; cook about 1 min. add broth & potato; cover & bring to a boil. reduce heat & simmer until potato is tender, about 5 min.

stir in kale & chorizo; cover & bring to a boil. reduce heat; simmer until kale is tender, 3 to 5 minutes. season with salt