Place lamb in a large bowl, toss with 2 tablespoons of the olive oil
In a large resealable bag, toss together the paprika, turmeric, cumin, cayenne, cinnamon, cloves, cardamom, salt, ginger, saffron, garlic powder, and coriander; mix well
Add lamb to the bag, and shake to coat well. Refrigerate overnight.
Heat remaining oil in a large saucepan over medium-high heat
Cook lamb, in batches, until well browned. Remove from pan
Add onions and carrots and cook for 5 minutes
Stir in the garlic and ginger and cook until fragrant.
Return the lamb to the pan with the lemon zest, chicken stock, tomato paste and honey
Bring to the boil and then reduce heat to low. Cover and simmer for 1½ to 2 hours, stirring occasionally, until the meat is tender.
If the consistency of the tagine is too thin, you may thicken it with a mixture of corn flour and water during the last 5 minutes