Chianti Burgers with Caramelized Onions

• 1/2 cup white wine vinegar
• 1/4 cup sugar
• One 14-ounce can diced tomatoes
• 1 small red bell pepper, finely chopped
• 1 teaspoon finely grated fresh ginger
• Kosher salt
• Freshly ground pepper
• 2 tablespoons extra-virgin olive oil, plus more for brushing
• 2 medium onions (1 pound), thinly sliced
• 1 tablespoon minced sage
• Four 4-inch focaccia squares, split horizontally
• 1 1/2 pounds ground beef chuck
• 4 slices of young Pecorino cheese (4 ounces)

1. In a small saucepan, combine the vinegar and sugar and cook over moderate heat, stirring occasionally, until a medium amber caramel forms, 8 to 10 minutes.
2. Carefully add the tomatoes and red pepper and cook, stirring occasionally, until the mixture is very thick, about 20 minutes.
3. Transfer to a blender and puree.
4. Strain the ketchup through a sieve.
5. Stir in the ginger and season with salt and pepper.
6. In a large skillet, heat the 2 tablespoons of olive oil.
7. Add the onions and cook over moderately low heat, stirring, until golden, 15 minutes.
8. Stir in the sage and keep warm.
9. Preheat the oven to 475.
10. Heat a griddle.
11. Lightly brush the griddle with oil and toast the focaccia on it until lightly golden, 1 to 2 minutes per side.
12. Transfer the focaccia to plates.
13. Gently shape the ground beef into four 1/2-inch-thick patties and season with salt and pepper.
14. Griddle the burgers over high heat until browned, 1 minute per side.
15. Transfer to a baking sheet and top each one with a slice of cheese.
16. Bake for 5 minutes for medium-rare.
17. Set the burgers on the focaccia and top with the onions and a dollop of the ketchup.
18. Close the burgers and serve.

white wine vinegar, sugar, tomatoes, red bell pepper, ginger, kosher salt, freshly ground pepper, extravirgin olive oil, onions, sage, focaccia squares, ground beef chuck, pecorino cheese

Taken from www.foodandwine.com/recipes/chianti-burgers-with-caramelized-onions (may not work)