Step 1: Make the Custard

1. In a saucepan over medium heat, whisk together the milk, heavy cream, and half of the sugar. Heat until steaming but not boiling.

2. In a separate bowl, whisk the egg yolks, cornstarch, remaining sugar, and salt until smooth.

3. Slowly pour a ladle of hot milk into the egg mixture, whisking constantly to temper the eggs.

4. Gradually pour the egg mixture back into the saucepan, whisking continuously.

5. Cook over medium-low heat, stirring constantly, until thickened (about 3–5 minutes).

6. Remove from heat and stir in the butter and vanilla extract. Let the custard cool slightly.

Step 2: Assemble the Banana Pudding

1. In a 9×13-inch dish or trifle bowl, layer vanilla wafers at the bottom.

2. Add a layer of banana slices, followed by a layer of warm custard.

3. Repeat the layers until all ingredients are used, finishing with custard on top.

Step 3: Add the Topping

Top with whipped cream or meringue, then chill for at least 4 hours (or overnight) to allow flavors to meld.

Step 4: Serve and Enjoy!

Serve cold or at room temperature, garnished with extra banana slices or crushed vanilla wafers.