Peel potatoes, cut in half and boil in vegetable stock.
Whilst potatoes are boiling, heat some vegetable oil in a frying pan and gently fry garlic, chilli, cumin, onion powder, turmeric and coriander powder until fragrant.
Add chopped tomatoes and season with salt. Cook until tomatoes have released their juices and broken down.
Sprinkle fenugreek leaves over tomatoes and cook for a further minute.
Mix cornflour with a small splash of cold water to form a paste. Add this to the tomato mix, combine then pour in vegetable stock. Bring to the boil then turn to simmer for a few minutes or until sauce thickens slightly.
Drain potatoes and cut them into bite-size pieces.
Gently mix potatoes into the spice sauce (you may need to reheat the sauce a little before adding potatoes). Cover and let it sit for 10 minutes so the potatoes can soak up the sauce.
Serve warm or refrigerate until needed and serve as a cold potato salad.