1 tablespoon olive oil
1 1/2 pounds lean ground beef
1 onion, diced
3 cloves garlic, minced
1 small head green cabbage, shredded
1 (28-ounce) can crushed tomatoes
1 cup tomato passata
1/4 cup sugar
1 lemon
1 teaspoon paprika
Salt and pepper, to taste
Heat the olive oil in a skillet set over high heat.
Add the beef and cook, breaking up with a wooden spoon, until browned.
Remove the beef from the skillet using a slotted spoon, and transfer to the slow cooker.
Drain off all but 1 tablespoon of the fat in the pan and discard.
Add the onion to the pan and cook, stirring occasionally, until browned.
Add the garlic, and cook until just fragrant, about 1 minute. Transfer to the slow cooker along with the beef.
Add the cabbage, tomatoes, tomato passata, sugar, lemon juice, paprika, salt and pepper to the slow cooker. Stir well to combine.
Cover and cook on low for 6 hours, until the cabbage is tender.