Step by step method

• Step 1

  Heat the oil in a medium saucepan over medium heat. Add the mustard seeds and cook for 30 seconds or until they begin to pop. Add the onion and garlic, and cook, stirring occasionally, for 8 minutes or until the onion is soft.

• Step 2

  Add the coriander, cumin, turmeric, cinnamon and nutmeg, and cook, stirring, for 1 minute or until fragrant. Add the lentils, potato and stock, and bring to the boil over medium-high heat. Reduce heat to low and cook, covered, for 20 minutes. Remove lid and cook, stirring occasionally, for a further 10 minutes or until all of the liquid evaporates. Set aside to cool for 20 minutes.

• Step 3

  Transfer the lentil mixture to the bowl of a food processor and process until a coarse paste forms. Taste and season with salt and pepper if necessary.