1.Combine pork, half the garlic, and all the onion, mint, egg white and breadcrumbs in medium bowl; season. Shape pork mixture into six patties; place on tray. Cover; refrigerate 30 minutes.
2.Heat large non-stick frying pan over medium heat; cook silverbeet, cabbage, spinach, pepper and remaining garlic, stirring, about 5 minutes or until greens wilt. Season to taste. Remove from pan; cover to keep warm.
3.Cook patties in same pan until browned both sides and cooked through. Remove from pan; cover to keep warm.
4.Add mustard, flour, stock and wine to pan; cook, stirring, until mixture boils and thickens. Strain sauce into small heatproof jug. Serve rissoles with greens and sauce.