1/4 cup sugar
1/2 cup white balsamic vinegar
1 medium red onion, thinly sliced
2 tablespoons extra virgin olive oil (EVOO)
1 1/2 pounds ground pork
Salt and ground black pepper
1 tablespoon fennel seeds
1 teaspoon red pepper flakes
3 cubanelle peppers (Italian frying peppers), seeded and thinly sliced
2 cloves garlic, finely chopped or grated
1/4 cup tomato paste
1/2 cup white wine
1 1/2 cups chicken stock
4 crusty rolls (such as a ciabatta or Kaiser roll), split and toasted
Place a small pot over medium-high heat with the sugar and white balsamic vinegar. Bring up to a bubble, stirring frequently to dissolve the sugar. Place the onions in a large heat-safe bowl and pour the sugar-vinegar mixture over them. Stir to combine and let the onions rest for at least 15 minutes. While the onions are resting, place a large skillet over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the ground pork to the pan, season with salt and pepper, and cook until golden brown, about 7-8 minutes, breaking the meat up with a wooden spoon or potato masher. Add the fennel seeds, red pepper flakes, peppers and garlic to the pan and cook until the peppers are tender, about 5 minutes. Add the tomato paste and cook until golden and aromatic, about 1 minute. Add the wine to the pan and scrape up any bits that may be stuck to the bottom of the pan. Cook until almost completely evaporated, about 2 minutes. Add the chicken stock to the pan and bring up to a bubble. Season with salt and pepper, and simmer until thickened to a Sloppy Joe consistency, about 10 minutes.
Serve the mixture up over the toasted buns and top with some pickled onions.