- 1 cup organic ketchup, preferably Heinz
- 2 tablespoons balsamic reduction, homemade or store-bought (such as Rachael Ray Balsamic Drizzle)
- 2 tablespoons EVOO – Extra Virgin Olive Oil, plus more for drizzling
- 2 large onions, thinly sliced
- Salt and pepper
- 1 1/2 pounds 85% lean ground beef
- 1/4 cup Chianti or other dry red wine
- 2 tablespoons chopped fresh rosemary
- 2 tablespoons thinly sliced sage leaves
- 2 large cloves garlic, grated
- Shaved young Pecorino, Gorgonzola or Fontina Val d'Aosta
- 4 5-inch squares focaccia, split horizontally
In a small bowl, mix the ketchup and balsamic reduction.
In a large skillet, heat 2 tablespoons EVOO, two turns of the pan, over medium-low. Add the onions and season with salt and pepper. Cook the onions, stirring occasionally, until deep golden and very sweet, about 35 minutes. (If needed, add some water to the skillet, to keep them moist.)
Preheat a cast-iron skillet or griddle over medium-high. In a medium bowl, combine the beef, wine, rosemary, sage and garlic; season. Form into 4 patties (thinner at the center for even cooking).
Drizzle the patties with some EVOO and cook, turning once, about 8 minutes for medium-rare. During the last minute of cooking, top the patties with the cheese; cover or tent with foil until the cheese melts.
Divide the burgers among the focaccia bottoms. Top each with the onions, balsamic ketchup and the focaccia tops.