Heat oven to 200C/180C fan/gas 6. Using a pestle and mortar, bash together the spices, herbs, garlic and some seasoning.
Spoon into a large bowl and stir in the lemon zest and juice, and the oil. Add the potatoes and toss together. Arrange, skin-side down, on 2 baking trays and bake for 30–40 mins until soft inside and crisp on the outside.