To make the syrup, combine sugar, water, honey and lemon juice in a sauce pan. Bring to a boil over medium high heat or until sugar dissolves. Reduce heat to low and cook without stirring for another 5 minutes. Remove from heat and let cool.
Preheat oven to 350F. Grease a 13″ x 9″ baking pan.
Trim phyllo dough to fit the baking pan. (I cut my pastry dough in half vertically, so each sheet fitted my pan perfectly. And I had 48 sheets after cutting.)
Place one phyllo sheet in the prepared pan and lightly brush with butter. Repeat with 9 more sheets until you have 10 sheets in the pan.
Mix walnuts and cinnamon. Spread 1 cup of the nut mixture on the butter sheets.
Repeat 2 more times. And finish with 10 buttered sheets.
The order is: 10 sheets / 1 cup nuts / 10 sheets / 1 cup nuts / 10 sheets / 1 cup nuts / 10 sheets
Use a sharp knife to cut into diamond or square shapes all the way to the bottom of the pan.
Bake for about 50 minutes until baklava is golden and crisp.
Remove baklava from oven and immediately spoon sauce over it. Let it sit for 4 to 6 hours or even overnight uncovered at room temperature. This helps the syrup to penetrate the layers.