1. Preheat the oven to 160°C/Fan 140°C/Gas 3. Fill a large pan with boiling water and return to the boil. Sprinkle in a good pinch of salt. Scrub the new potatoes and slice in half. Tumble into the pan, reduce to a simmer and cook for 10-15 mins, till easily pierced with the point of a knife.
2. While the potatoes simmer, pour the yogurt into a bowl. Peel and grate in 1 of the garlic cloves and the zest from the lemon. Combine with a little salt and pepper and set aside.
3. Trim the aubergines and cut into small pieces. Peel and finely slice the red onions. Trim and shred the chard stalks, and roughly chop the leaves. Pour 1 tbsp oil into a large, ovenproof frying pan (see our tip if your frying pan isn't ovenproof) and bring to a medium heat. Add the aubergines and onions to the pan with a pinch of salt and pepper. Fry for 8-10 mins, stirring occasionally, till softened.
4. Slide in the chard stalk and leaves along with 1 tbsp ground cumin and ¾ tbsp black onion seeds. Fry for a further 3-4 mins, till tender and wilted. Make 4 craters with a wooden spoon and carefully break in the duck eggs. Transfer the pan to the oven for 6-8 mins, till the eggs are just set.
5. While the eggs are cooking, finely chop the dill and peel and grate the remaining garlic clove. Trim the leaves off the radishes (you can keep them for salads or use them to make pesto), rinse the radishes, shake dry, and finely slice them. When the potatoes are ready, drain them and transfer to a bowl. Toss with the dill, garlic, radishes, lemon juice and 1 tbsp olive oil.
6. Remove the baked duck eggs from the oven and dollop on the garlic and lemon yogurt. Scatter over the remaining onion seeds, and serve with the dill and lemon potatoes.
7. Tip: No ovenproof pan? No problem. Simply fry the aubergine, onions, chard and spices as described above in an ordinary pan and transfer to a roasting dish before breaking in the eggs and baking.