Dice the bacon and onion, brown them in a large pan.

Once they are to your liking add the flour sugar and vinegar. Mix and bring to a simmer.

Add the kale. Toss the sweet and sour mixture over the kale. This will take a while if the kale isn't wilting you can add 1/4 cup of water to quicken the process. Cook until the kale is soft should take about 5-10 minutes.