2 tablespoons olive oil
1 onion, peeled and finely chopped
1/2 teaspoon salt, divided
2 garlic cloves, peeled and finely chopped
1 pound ground beef
1/2 cup red wine
1 (14.5-ounce) can Italian pear tomatoes, chopped
1 tablespoon tomato paste
1 1/2 teaspoons dried oregano
1/2 teaspoon red-pepper flakes
6 hamburger or other rolls, toasted
6 slices provolone cheese
Giardiniera (Italian-style pickled-vegetable relish), for serving

Heat the olive oil in a large skillet over medium-high heat. Add the onion and season with 1/4 teaspoon of the salt. Cook, stirring occasionally, until beginning to soften. Stir in the garlic and cook for 1 minute.

Add the ground beef, stirring it into onions and breaking it up; cook until browned. Stir in the wine, chopped tomatoes and paste, oregano, red-pepper flakes and remaining salt. Cook, stirring occasionally, until thickened. Taste for seasonings.

Serve mixture on the rolls, each topped with a slice of the provolone and a generous helping of the giardiniera.

Makes 6 servings.