How to Make It
Grind 1/4 cup of the walnuts to a powder in a food processor. In a small saucepan, melt the butter over moderately low heat. Add the onion; cook until translucent, about 5 minutes. Add the garlic and cook, stirring, 30 seconds longer. Stir in the cloves, cinnamon, cayenne, and 1/4 teaspoon of the salt. Add the flour and stir to combine. Whisk in the broth and simmer until starting to thicken, about 3 minutes. Add the ground walnuts and simmer 1 minute longer. Remove from the heat and stir in the lemon juice, Parmesan, and parsley.
In a large nonstick frying pan, heat the oil over moderately high heat. Season the turkey with the remaining 1/4 teaspoon salt and the pepper. Cook the turkey cutlets until just done, 1 to 2 minutes per side. Serve with the walnut sauce, sprinkling the additional nuts over the top.
Roasted asparagus and sautéed peppers are vegetables that taste particularly good with both walnuts and Parmesan cheese.