Put all the marinade ingredients in a mixing bowl apart from the mushrooms, and stir to combine. Then add the mushrooms and mix well to coat the mushrooms in the marinade evenly.
Set aside and leave to marinate for an hour or cover overnight in the fridge.
Once marinated and ready to cook, preheat the oven to 400 °F (200 °C).
Put the mushrooms on a non-stick or lined baking sheet and bake in the oven for around 20 minutes until starting to brown and the excess water has cooked from the mushrooms.
For the curry:
Blend. Put the garlic, ginger, soaked cashews, and tomatoes in a blender and blend until smooth.
Cook the curry. In a large saucepan or dutch oven, add a good splash of oil and bring to medium heat. Add the onion and gently fry for 5-10 minutes until completely soft and starting to brown.Sprinkle in the spices and fry for a couple of minutes until fragrant.
Stir in the tomato puree, then pour in the blended cashew paste and stir well. Pour in the water, then bring the sauce to a simmer.
Pop the carrots into the pan and simmer for around 15 minutes until the carrots are tender.
Add the baked mushrooms, stir well and simmer for another 5 minutes.
Optionally sprinkle in 1 teaspoon of sugar and season with salt to taste.
Finally, add the peas and bring them back to a simmer for a couple of minutes, so the curry is piping hot.