Remove fillo from refrigerator, and let it come to room temperature.
Preheat oven to 375 degrees.
On a large baking sheet lined with foil, toast the walnuts and pecans until golden in color. Remove from heat, and let cool. Once nuts have cooled down, place in Cuisinart and chop nuts until they come to a fine mix.
In a bowl, mix the pumpkin spice, 2 teaspoons of sugar, and nut mixture.
Butter a large 9 * 13 pan baking dish and set aside.
Prepare fillo dough sheets. Unroll the sheets and make sure you have a slightly damp cloth around so you can cover the rest of the fillo sheets. Place one fillo sheet over the bottom of the baking dish. Lightly brush with butter, and repeat process with 5 sheets.
Spread about 1/3 cup of the pumpkin puree over the fillo sheets. Spread the nut mixture over the pumpkin puree and repeat process with fillo dough. (You should have 2 layers of pumpkin and of nut mixture.)
After you place that last fillo sheet over the top, brush with butter. Cut the layers into criss cross pieces, making diamond shaped baklava.
Bake for about 1 hour, making sure the baklava is golden brown on the top.
In a medium pot over medium heat cook the water, sugar, and honey. Bring to a boil then slowly lower the temperature to low heat. Cook syrup for about 20 minutes or until the syrup becomes thick.
Once baklava comes out of oven, pour syrup over the top and let sit for about 5 hours.
Serve with a sprinkle of cinnamon powder over the baklava.