Combine walnuts, sugar, cinnamon, and cloves in a bowl. Set aside.
Make the syrup: combine sugar, honey, water, lemon peel, cinnamon stick, and cloves in a saucepan. Bring to a boil, reduce heat, and simmer 10 minutes. Remove aromatics and set aside to cool completely. The syrup must be cool when it meets the hot pastry.
Clarify the butter: melt over low heat, skim foam, pour off clear fat, discard milk solids.
Preheat oven to 325°F (160°C). Butter the baking pan generously.
Layer 8–10 phyllo sheets in the pan, brushing each with butter. Keep unused phyllo covered with a damp cloth.
Spread half the walnut mixture evenly over the base. Press down lightly.
Add 4–6 more buttered phyllo sheets on top.
Spread remaining walnut mixture evenly.
Layer remaining phyllo sheets, buttering each generously. Finish with a generous final butter brushing on top.
Cut all the way through to the bottom of the pan into diamond shapes before baking. Use a sharp knife with a light sawing motion.
Bake at 325°F for 45–55 minutes until deep golden brown. Cover loosely with foil if top browns too fast in the last 15 minutes.
Remove from oven. Pour the cooled syrup slowly and evenly over the entire surface of the hot baklava. You will hear it sizzle and absorb.
Cool at room temperature for at least 4 hours before serving. Do not refrigerate.