Spicy Greens

1 large onion, diced
1 tbsp olive oil
1 bunch greens
2 tsp vinegar
1/4 tbsp crushed red pepper flakes

Saute the onion in the oil in a large skillet or saucepan on low heat for about 10 minutes, until transluscent. While the onion sautees, thoroughly rinse the greens. Remove and discard any large stem ends and coarsely chop the leaves. Add the moist greens to the onions and cook, covered for about 5 minutes, stirring occasionally, until the leaves are wilted but still bright green. Stir in the vinegar and red pepper flakes. Add salt and pepper to taste and serve immediately or at room temperature.