Ingredients

• 4 bone-in, skin-on chicken thighs (about 700g)
  

• Kosher salt plus freshly ground black pepper, to taste
  

• 1 tablespoon olive oil
  

• 1 medium yellow onion, finely chopped
  

• 1 tablespoon olive oil
  

• 1 medium yellow onion, finely chopped
  

• 3 garlic cloves, crushed
  

• 1 teaspoon fennel seed, lightly crushed
  

• 1/4 teaspoon chile flakes, or to taste
  

• Finely grated lemon zest, from 1 lemon
  

• 350ml chicken stock (homemade or store-bought), or more as needed
  

• 250g (packed) kale (curly or Tuscan)

• 1 jar of white beans or butter beans

• 400g diced tomatoes, drained of juice