Long-Cooking Onion Sauce

• 4 pounds onions, preferably sweet varieties like Walla Walla or Vidalia (about 8 onions)
• 2 tablespoons olive oil
• 1 tablespoon unsalted butter
• 1 shallot, peeled and thinly sliced
• 2 cloves garlic, peeled and thinly sliced
• 1/2 cup white wine
• 1/2 teaspoon apple-cider vinegar
• 1 tablespoon chopped sage leaves
• Kosher salt and freshly ground black pepper to taste

1. Peel, quarter and thinly slice the onions.
2. In a large heavy kettle, heat the olive oil and butter over medium heat and add the onions.
3. Cook, stirring frequently, until the onions begin to turn golden, about 1 hour.
4. Lower the heat if the onions stick to the bottom.
5. Add the shallot and garlic and continue cooking, stirring often, until the onions are a deep golden color, 20 to 30 minutes more.
6. Add the wine and vinegar and cook until the liquid has evaporated.
7. Add the sage and season with salt and pepper.
8. Serve as a sauce with duck, pork or roasted meats.

onions, olive oil, unsalted butter, shallot, garlic, white wine, applecider vinegar, sage, kosher salt

Taken from cooking.nytimes.com/recipes/10595 (may not work)