Banana-Walnut Napoleons

3 tbsp. sugar
1/8 tsp. salt
1/8 tsp. cinnamon
1/8 tsp. nutmeg
1 large egg yolk
1 cup milk
2 tbsp. cornstarch
1½ tsp. walnut oil
4 (18 x 14 each) sheets frozen phyllo dough, thawed

Caramel-Walnut Sauce:
1/4 cup packed brown sugar
2 tbsp. water
1 tbsp. walnut oil
1 ripe banana, peeled and cut into 16 slices
4 tsp. finely chopped walnuts, toasted

To prepare filling, combine first 4 ingredients in a small saucepan, stirring
well with a whisk. Add egg yolk, stirring well. Combine milk and
cornstarch, stirring with a whisk until well blended. Slowly whisk
cornstarch mixture into the egg mixture. Bring to a boil over medium heat,
stirring constantly with a whisk. Remove from heat. Stir in 1½ tsp. walnut
oil. Pour filling into a bowl. Place plastic wrap on surface; cool to room temp.

To prepare Napoleons, place 1 phyllo sheet on a large cutting board or work
surface (cover remaining dough to prevent drying); lightly coat with
cooking spray. Place another phyllo sheet on top; lightly coat with cooking
spray. Repeat layers with remaining 2 phyllo sheets and cooking
spray. Gently press phyllo layers together; lightly coat top sheet with
cooking spray. Cut phyllo stack in half lengthwise. Cut each half crosswise
into 4 rectangles. Carefully place rectangles onto a nonstick baking sheet
coated with cooking spray. Bake at 350° for 10 minutes or until crisp and
lightly browned. Remove phyllo stacks from pan; cool completely on a wire rack.

To prepare sauce, combine the brown sugar and water in a small saucepan; place
over medium-high heat. Bring mixture to a boil; reduce heat, and simmer
3 minutes. Remove from heat; stir in 1 tbsp. walnut oil. Add banana; stir
gently to combine.

To assemble, place 1 phyllo stack on each of 4 plates; top with 1/4 cup
filling. Place banana slices on each serving; cover with 1 phyllo stack.
Drizzle brown sugar mixture evenly over Napoleons. Sprinkle with walnuts.