1 tablespoons extra-virgin olive oil
1/2 medium onion, finely chopped
2 garlic cloves, finely chopped
1/2 teaspoon crushed red pepper flakes
Half a pound collard greens, ribs and stems removed, leaves sliced crosswise into 1-inch-thick strips
1 cup low-sodium broth (chicken or vegetable) or water
2 tablespoons apple cider vinegar
1/2 teaspoon sugar
Kosher salt, freshly ground pepper
Heat oil in a large heavy pot over medium heat until shimmering.
Add diced onion and cook, stirring occasionally, until gold and soft, about 5 min.
Add garlic and red pepper flakes and cook, until fragrant, about 30 seconds, stirring regularly.
Add collard greens to pot by the handful, making sure each batch wilts slightly before adding more.
Add broth to pot and bring to a simmer.
Cook, stirring often, until greens wilt and shrink to half their size, about 4 minutes.
Lower heat to medium-low, cover pot partially, and simmer until collard greens are tender and there’s very little liquid left over, about 30 minutes. Stir occasionally.
Add in vinegar and sugar and cook until sugar dissolves, about 1 minute. Season with salt and pepper or adjust vinegar, sugar, and red pepper flakes until you’re satisfied!