Heat your oven to 200°C/Fan 180°C/Gas 6. Spoon the yogurt into a shallow dish. Measure out 2 tsp of the spice mix and stir into the yogurt. Season with salt and pepper. Add the dab. Turn to coat. Leave to marinate for 10 mins. Fill and boil the kettle.
Rinse the rice under cold running water. Tip into a small pan. Pour in 300ml hot water from the kettle. Cover. Bring to the boil. Turn the heat right down. Simmer gently for 15 mins.
While the rice cooks, trim and peel the beetroots. This can get messy, so you might want to pop some rubber gloves on. Coarsely grate the beetroot onto a plate. Pop to one side.
Grate or pare the zest from the lemon. Juice it. Rinse the parsley. Pat dry with kitchen paper. Finely chop the leaves. Rinse the baby red chard.
Lightly oil a baking tray. Lift the fish out of the marinade. Pop it on the tray. Bake for 20-25 mins till the fish is golden and flakes easily when you press it with a fork.
Stir the beetroot, lemon zest and juice into the rice. Pop the lid back on. Simmer for another 5-10 mins till all the water has been absorbed. Take off the heat. Steam, lid on, for 5 mins to finish cooking the rice and beetroot.
Stir the chard into the rice till it wilts. Taste and season. Serve the rice with the baked fish, sprinkled with chopped parsley.