Preheat your oven to 350°F (175°C) and line two baking trays with parchment paper.

In a large mixing bowl, beat the softened butter and sugar together until light and fluffy, about 3-4 minutes.

Add the egg yolks and vanilla extract, mixing until well combined, about 1-2 minutes.

Gradually add flour and salt, mixing until the dough forms large crumbles, about 2-3 minutes.

Add milk to achieve the right dough consistency, starting with 2 tablespoons.

Transfer the dough into a piping bag fitted with a large star tip.

Pipe the dough into rosette shapes on the prepared trays, leaving space for expansion.

Bake for 13-15 minutes until edges are golden. The center should remain soft.

Let the cookies cool on trays for about 5 minutes, then transfer to wire racks to cool completely.