To begin with, chop the sweet potato and pop it in a hot oven.
I prefer to steam the chicken breasts (make sure they are free-range), but you can fry them now if you prefer, or begin cooking in the oven with the sweet potato. Steaming is obviously the healthiest way of cooking them, but this is really up to you.
If you are having the curry with rice, you may want to start this off now.
Prepare the onions. They need to be finely chopped. I prefer to roughly chop them in the food processor.
Add a little water to a large, deep pan and add the onions. This eliminates the need for oil making the dish even healthier.
Chop the apple, and add to the pan.
Put the pepper, tomatoes, spinach, kale, ginger, and curry powder into the food processor and blend briefly and roughly.
After about 5 minutes, when onions turn translucent, add the garlic.
Add the processed mixture and stir on a low heat.
Add the mushrooms.
Add the chopped sweet potato from the oven.
Add the chicken if you have not already done so.
Leave to simmer for 20-30 minutes, stirring occasionally.
Serve with brown rice and garnish with a fresh coriander. A spoonful of plain yoghurt will go perfectly with the dish too.