Step 1: Preheat oven to 350°F (175°C). Grease a 9×13 inch baking dish.
Step 2: In a medium bowl, combine diced apples, sugar, cinnamon, nutmeg, and cloves. Mix well and set aside.
Step 3: In another bowl, mix chopped walnuts and pecans.
Step 4: Place one sheet of phyllo dough in the baking dish, brush lightly with melted butter. Repeat with 8 more sheets, brushing each with butter.
Step 5: Spread half of the apple mixture evenly over the phyllo layer.
Step 6: Sprinkle half of the nut mixture over the apples.
Step 7: Add 4 more phyllo sheets, brushing each with butter.
Step 8: Repeat layers with remaining apples and nuts.
Step 9: Top with remaining phyllo sheets (about 8-10), brushing each with butter. Cut into diamond or square shapes with a sharp knife.
Step 10: Bake for 30 minutes or until golden brown and crispy.
Step 11: While baking, combine maple syrup, water, lemon juice, and vanilla in a small saucepan. Simmer for 5 minutes.
Step 12: Remove baklava from oven and immediately pour hot maple syrup mixture evenly over the top. Let cool completely before serving.