Serve the marmalade with crackers or bread and a firm cheese, such as cheddar or manchego.
2 lemons, thinly sliced and seeded, slices quartered (2 cups)
1 1/2 pounds green tomatoes (about 4 large tomatoes), cored and cut into 1/2-inch dice
1 cup sugar
1 tablespoon fresh lemon juice
1/2 teaspoon coarse salt
1/4 cup water
Place lemon slices in a medium pot, and add enough cold water to cover by 2 inches. Bring to a boil, and drain.
Place lemons, tomatoes, sugar, lemon juice, salt, and water in a large saucepan over medium heat. Bring to a simmer, stirring until sugar dissolves, and cook until lemon slices are translucent and syrup has thickened, 30 to 35 minutes. Let cool. Cover, and refrigerate for up to 1 week.