chilli soaking liquid, as needed

Remove the stems and seeds from the chillies. Pour over hot (not boiling) water and let soak for about 10 minutes.

Lightly toast the cumin and coriander seeds in a dry pan until fragrant.

Drain the chillies and place them in a blender with the garlic, spices, salt and lemon juice.

Blend until smooth, adding the olive oil in a thin stream. Add a little soaking liquid if needed to reach a thick paste.

Taste and adjust salt or acidity. Transfer to a clean jar and lightly cover the surface with olive oil.