Ingredients

1 pound kale, tough stems and center ribs removed, leaves cut into thin ribbons
4 teaspoons olive oil, divided
1 pound uncooked chicken sausages
1 medium onion, peeled, halved lengthwise and thinly sliced into crescents
12 cup low-sodium chicken broth
2 cloves garlic, minced
14 teaspoon red pepper flakes
2 teaspoons finely grated lemon rind
1 teaspoon lemon juice
14 teaspoon salt