Remove the core from the cabbage head. Bring a large pot of salted water to a boil and submerge the cabbage. After 3-4 minutes, use tongs to peel off softened outer leaves. Return cabbage to water and repeat until you have 12-14 leaves. Trim the thick rib from each leaf.

In a large bowl, combine ground beef, cooked rice, diced onion, minced garlic, egg, salt, pepper, and paprika. Mix gently by hand until just combined.

Place one cabbage leaf on work surface with stem end toward you. Add 2-3 tablespoons filling to lower third of leaf. Fold bottom edge over filling, fold in sides, and roll tightly. Place seam-side down. Repeat with remaining leaves and filling.

Whisk together tomato sauce, broth, brown sugar, and lemon juice. Scatter leftover cabbage scraps in bottom of large Dutch oven. Arrange cabbage rolls seam-side down in pot.

Pour sauce over rolls until nearly covered. Bring to simmer over medium heat, then reduce to low. Cover and cook 75-90 minutes until cabbage is very tender and filling reaches 165°F. Add water or broth if sauce reduces too much during cooking.