Cut chops in half. Place flour in a plastic bag and season with salt and pepper. Place chops in bag and shake well to coat. Transfer chops to a plate. Reserve flour.
Preheat oven to 130°C. Place onions, potatoes and carrots in an ovenproof dish. Top with half the chops. Repeat layers with remaining onions, potatoes, carrots and chops.
Whisk reserved flour, tomato paste and 2 tablespoons cold water in a large jug until well combined. Slowly add boiling water, whisking constantly. Add stock cubes and parsley. Stir to dissolve stock cubes.
Pour flour mixture over chops. Cover and cook for 4 hours or until meat tender and sauce thickened. Sprinkle with mint and serve.
