Add the parsley, dill, jalapeno and green onions into a blender and process until roughly combined. Add the salt, yogurt and egg yolks and process on high until the sauce is green and smooth.
Add the lamb to a large skillet set over medium high heat and cook, stirring occasionally until the lamb is browned and cooked through. Remove any excess fat from the skillet. Add the coriander, garlic, salt and pepper and currants (if using) cook for another 3min. on low heat.
Cook the pasta according to the package directions in a large pot with well salted water. Once cooked, drain the pasta and return it to the pot.
Set the pasta pot over medium-low heat and pour the yogurt sauce over the pasta. Cook, stirring often, until the sauce has thickened and sticks to the pasta. Stir in the lemon juice and cooked lamb.
Scatter the toasted walnuts and lemon zest over the top and serve.
