Heat neutral oil in a large pot over medium heat. Add onion and cook 5–6 minutes until soft. Add garlic and ginger and cook 2 minutes. Add smoked paprika and onion powder and stir 30 seconds. Add gochujang paste and cook 1 minute, stirring into the aromatics.
Add potato chunks and stir to coat in the gochujang base. Pour in vegetable broth, water, and soy sauce. Bring to a boil then reduce to a steady simmer. Cook uncovered for 15–18 minutes until potatoes are completely tender when pierced with a fork.
Stir in drained white beans and simmer 3–4 minutes. Add chopped kale, press into the liquid, and cover. Cook 3 minutes until wilted. Remove lid, stir to combine.
Stir in rice vinegar and sesame oil off the heat. Taste and adjust — add more soy sauce for salt, more gochujang for heat, or a teaspoon of honey to reduce heat. Add a splash of water if the stew has thickened too much.
Ladle into bowls. Top with sesame seeds, spring onions, and a drizzle of sesame oil. Serve with rice or bread and a spoonful of yogurt on the side for those who want to cool the heat.
