Follow these simple steps to make your tiramisu:

1. Mix Egg Yolks and Sugar: In a medium saucepan, whisk together the egg yolks and granulated sugar until well combined.

2. Add Milk: Gradually stir in the milk, then place the saucepan over medium heat. Cook the mixture, stirring constantly, until it thickens slightly and coats the back of a spoon (about 5-7 minutes).

3. Cool the Mixture: Remove from heat and let it cool slightly before transferring it to a mixing bowl. Allow it to cool to room temperature.

4. Whip Cream: In a separate bowl, whip the heavy cream until soft peaks form. Be careful not to over-whip.

5. Combine Mixtures: Gently fold the mascarpone cheese into the cooled egg mixture until smooth. Then, carefully fold in the whipped cream until fully combined.

6. Prepare Coffee Mixture: In a shallow dish, mix the cooled brewed coffee and coffee liqueur (if using).

7. Dip Ladyfingers: Quickly dip each ladyfinger into the coffee mixture. Don’t soak them too long; they should be moist but not falling apart.

8. Layer Tiramisu: In a rectangular dish, arrange half of the soaked ladyfingers at the bottom. Spread half of the mascarpone mixture over the ladyfingers.

9. Repeat Layers: Add another layer of dipped ladyfingers, then top with the remaining mascarpone mixture.

10. Chill: Cover the dish and refrigerate for at least 4 hours, but overnight is recommended for better flavor.

11. Serve: When ready to serve, dust the top with cocoa powder and, if desired, sprinkle with dark chocolate shavings.