Preheat the oven to 350°F (180°C) and grease a 9×13 inch baking dish with melted butter.
Add the chopped walnuts, sugar, and cinnamon into a large mixing bowl and mix together using a spatula. Make sure the nuts are chopped finely, a quick way to do this is to use a food processor.
Place one sheet of phyllo pastry dough in the bottom of the buttered baking dish, then brush the top with the melted butter.
Repeat this step by brushing nine more sheets of phyllo pastry and layering them onto each other.
Spread half of the walnut mixture over the phyllo dough, then add one sheet and brush with butter.
Repeat by layering seven phyllo sheets and brushing each one with butter. Then, spread the remaining nut mixture over the top.
Add eight more buttered sheets on the top, then using a sharp knife, cut the into squares or diamond shapes.
Place into the oven and bake for 55-60 minutes or until golden on top.
Prepare the honey syrup: Add the water, 1 cup of sugar, honey, lemon juice, and lemon rind into a pot and bring to a boil, then reduce the heat and simmer for 15 minutes.
Once the baklava is baked, remove it from the oven, remove the lemon rind, and pour the syrup over the top. Allow the honey syrup to seep into the baklava pastry for one hour before serving.
Enjoy your homemade Greek Baklava!