Layered dessert of vermicelli and custard

Ingredients:

**For the vermicelli layer:**
– 200 grams vermicelli (grated phyllo dough)
– 1/2 cup unsalted butter, melted
– 1/2 cup chopped walnuts or pistachios
– 1/4 cup granulated sugar
– 1 teaspoon ground cinnamon

**For the custard layer:**
– 4 cups milk
– 1 cup granulated sugar
– 1/2 cup cornstarch
– 2 teaspoons vanilla extract
– 1/4 teaspoon salt

**For the topping:**
– Chopped nuts (optional)
– Powdered sugar (optional)

Instructions: