For the marinade, mix the soy sauce, 1½ teaspoons of the red tea leaves, garlic and ginger in a small bowl until well blended. Place the sea bass fillets in large, non-metal dish. Add the marinade, turn to coat well and refrigerate for 30 minutes.
Line a large roasting pan with foil. Mix the remaining 2 tablespoons of red tea leaves with the rice and sugar and spread evenly on the bottom of the pan. Put a metal rack in the pan and place the fish and marinade on a disposable pie plate. Place the pie plate on the rack and cover the roasting pan tightly with foil.
Bake on the lowest rack in a pre-heated oven 450°F (230°C, Gas Mark 8) for 30 minutes or until the fish flakes easily with a fork.
Meanwhile, melt the butter in a medium sauté pan on a medium heat. Add the bread cubes and sprinkle the bread with ground cinnamon. Sauté for 5 minutes or until bread cubes are lightly ?toasted.
Remove bread cubes from the pan, add plum slices and cook until they begin to caramelise, stirring occasionally. Add the jam, water and juices that have collected in the pie plate from the cooked fish; cook and stir gently to glaze the plums.
To serve, spoon glazed plums onto each of 4 plates, top with croutons and sea bass fillets. Sprinkle with spring onion.
