In a large mixing bowl, whisk the egg yolks and sugar together until pale and fluffy, about 3-4 minutes.

In a small bowl, combine the powdered gelatin with 8 tablespoons of boiling water, stirring until completely dissolved.

In a saucepan, combine the milk and vanilla extract. Heat over medium-low until it comes to a gentle boil, around 5-7 minutes.

Gradually whisk the hot milk mixture into the egg yolk mixture, pouring in slowly while continuously whisking, about 2 minutes.

Return the combined mixture to the saucepan over medium-low heat. Cook while whisking constantly for about 2 minutes until slightly thickened.

Once the custard has cooled slightly, stir in the dissolved gelatin mixture until fully combined, about 1-2 minutes.

Allow the custard mixture to cool to room temperature, then fold in the pre-whipped heavy cream until smooth.

Pour the mixture into greased molds, smooth the tops, cover with plastic wrap, and refrigerate for at least 6 hours or overnight.

To serve, dip molds briefly in hot water to loosen, invert onto plates, and garnish with fresh berries.