In a small saucepan, combine the granulated sugar and water over medium heat. Stir until the sugar dissolves, then bring to a gentle boil and cook until it reaches 240°F (115°C).

In a mixing bowl, vigorously beat the egg yolks using a stand mixer or handheld whisk until thick and pale.

Once the syrup is ready, slowly drizzle it into the whipped egg yolks while mixing at low speed.

Gradually increase the mixer speed to high and whip the mixture until it cools to room temperature.

With the mixer on medium, add the softened butter one tablespoon at a time until well incorporated.

Finally, mix in the vanilla extract and a pinch of salt to complete the frosting.