Mushroom moussaka

What you need:

• 2 eggplants, sliced lenghtways
• 2 potatoes, cut into thin slices 
• 2 tablespoons olive oil 
• 1 onion, finely chopped 
• 1 clove garlic 
• 500g brown mushrooms, sliced 
• 1 tin white beans (like cannellini beans)
• 1 tin chopped tomatoes 
• ½ teaspoon sugar
• 2 tablespoons butter
• 1/3 cup plain flour
• 2 cups milk
• 1/3 cup Greek yoghurt 
• 1 egg, lightly beaten
• ¼ cup grated Parmesan cheese 

What to do:

1. Preheat oven to 220°C. Line a large baking sheet with tin foil, brush with olive oil and lay the egg plant and potato in a single layer on the sheet. Sprinkle with salt and pepper and bake for 20 minutes.
2. Meanwhile, fry the onion over medium heat in a little olive oil in a large frying pan over medium heat until golden. Add the garlic and fry for another minute. Increase the heat and add the mushrooms. Fry till soft, then add the tinned beans and tomatoes. Reduce the heat and simmer for 10 minutes then stir in the sugar.
3. Melt the butter over low heat in a large saucepan. Add the flour and cook for one minute. Remove from the heat and stir in the milk. Use a balloon whisk to ensure there are no lumps. Return to the heat and stir constantly until sauce boils and thickens. 
4. Reduce the heat and simmer for two minutes. Let cool slightly, then stir in the yoghurt, egg and Parmesan. Reduce the oven temperature to 180°C. Grease a shallow, heatproof dish or four ramekins. Spoon a layer of the mushroom and bean mixture into the base of the dish or dishes. Add a layer of eggplant, then a layer of potato and finish with a layer of white sauce. Bake for 30 to 35 minutes until slightly browned on top.