Heat oil:
Add olive oil to a large pan over medium heat.
Sauté onion:
Add sliced onion and cook until soft and lightly golden.
Add garlic & chili flakes:
Stir in garlic and red chili flakes; cook for 1–2 minutes.
Pan-fry beans:
Add cooked beans and cook for 5–7 minutes, stirring occasionally, until slightly crispy.
Add kale:
Toss in chopped kale and mix well with the beans.
Cook until wilted:
Cook for another 3–5 minutes until kale softens.
Season:
Add salt and black pepper to taste.
Serve hot:
Serve warm as a main dish or a side with bread or rice.