Peel and finely dice the shallots. Peel garlic and chop finely. Peel ginger and grate finely. Wash tomatoes, grate dry and cut into cubes. Clean the chillies, cut lengthwise, wash and remove the seeds.
Cut the pod into small pieces and cover about half of it and put it in a cool place. Peel and wash the cucumbers, cut them in half lengthwise and scrape out the core. Cut the cucumbers into slices about 0.5 cm thick.
Heat the oil in a wide saucepan. Stir-fry the mustard seed briefly while stirring. Add the garlic, shallots, ginger and chilli and fry until transparent. Press the cardamom and add with the tomatoes. Steam for about 1 minute while stirring.
Sprinkle with sugar, curry and turmeric, add cinnamon. Add 200 ml water. Season with salt and simmer at low heat for about 5 minutes. Add cucumber and coconut milk. Simmer for another 8-10 minutes.
Prepare rice in boiling salted water according to package instructions.
Meanwhile roast the cashew nuts in a pan without fat for 2-3 minutes. Let it cool down on a flat plate and chop it roughly. Wash coriander, shake dry, pluck off leaves and, except for a few for garnishing, chop coarsely.
Season curry with lime juice and salt. Arrange curry in deep bowls, add rice. Sprinkle cashews, chopped coriander and remaining chilli over rice and curry. Garnish with coriander leaves.