Heat oil in pan; cook onion, stirring, until soft.
Add cumin and rind to pan; cook until fragrant.
Stir in undrained crushed tomatoes.
Bring to boil; simmer, stirring occasionally about 5 minutes or until mixture thickens slightly.
Meanwhile, cook beef, in batches, in separate large heated oiled pan until browned all over and tender; stir in tomato mixture, almonds and mint.