To prepare spice blend, combine first 9 ingredients.
To prepare tagine, heat oil in a Dutch oven over medium heat. Add cabbage and the next 8 ingredients (cabbage through ginger); cook 3 minutes, stirring frequently. Stir in spice blend; cook 1 minute, stirring constantly. Add rind, broth, and tomatoes; bring to a boil.
Reduce heat; simmer, uncovered, 40 minutes or until lentils are tender. Stir in juice. Serve over couscous.