Preheat oven to 350 F. Spread the nuts out on a cookie sheet and bake until toasted and fragrent. About 5-8 minutes.
Place nuts in food processor and pulse with brown sugar and cinnamon until texture is medium-fine. Set aside.
Lay out your thawed phyllo dough on the counter and lay a damp tea towel on top. This will prevent the dough from drying out. Every time you pull off the layers you need just place the damp towel over the rest.
Butter a 9×13 pan with melted butter and a pastry brush. Use this for every layer of dough.
Set two sheets into the pan.
Butter the top.
Place two more sheets of dough in the pan.
Butter the top.
Again place two more sheets in the pan. This will make 6 sheets in the pan. Butter the top.
Sprinkle ⅓ of the nut mixture on top with the apples.
Place two sheets of dough on top and butter.
Repeat the process until you run out of nuts. I added pears to two layers of nuts and had 3 layers of nuts total. Make sure you have at least 4-6 sheets of dough as your final top layer.
Using a sharp knife, slice the baklava in a diagonal pattern. Butter the top
Bake for 45 minutes or until golden brown.