Add all the curry paste ingredients to a blender and pulse until smooth. Don't worry if it smells a bit odd at this point, it hasn't been cooked yet!
Spray the saucepan with low calorie cooking spray and place over a medium heat. Add the paste and cook it gently for two minutes.
Add 100ml of water, carrots and sliced pepper to the saucepan and stir well. Cook for 5 minutes.
Add the potatoes and stir well again to coat in the paste. Cook for 3 minutes.
Add the coconut milk, chopped tomatoes and peanut butter powder. Stir well and bring to the boil. Then reduce to a simmer and leave with the lid off for 20 minutes. The potatoes and carrots should be tender, and the sauce will be rich.
Season with salt and pepper to taste and serve with a side of your choice.