Heat large skillet over medium-high heat. When pan is hot, add 6 slices bacon (chopped) and cook until bacon is just crisp, approximately 5 to 6 minutes. Stir often to prevent bacon sticking and burning.
When bacon is crispy, add ½ of one white onion (diced) to skillet. Cook, stirring occasionally, until onion has softened, approximately 5 minutes.
When onion has softened, add 2 16-ounce cans green beans, ½ cup low-sodium chicken broth, 3 cloves garlic, 1 tablespoon unsalted butter, 1 tablespoon red wine vinegar, 1 teaspoon sugar, ½ teaspoon salt, and ¼ teaspoon freshly cracked black pepper to skillet. Stir to fully incorporate ingredients.
When ingredients are fully incorporated, reduce heat under skillet to low. Cover skillet with lid and simmer until green beans are tender, approximately 10 minutes.
Taste and add salt and/or pepper as needed, then transfer green beans to serving dish or divide into individual portions and serve warm.