Brown the butter

• Melt a portion of the butter in a saucepan over medium heat.
• Cook until the milk solids turn golden brown and nutty, then set aside to cool.

Make the cookie dough

• Cream the softened butter with the granulated sugar and powdered sugar until pale and fluffy.
• Beat in the egg yolk and vanilla extract.
• Fold in the flour, cornstarch and salt until a smooth dough forms.

Chill the dough

• Flatten the dough into a disc, wrap it and refrigerate until firm.

Shape the cookies

• Roll the dough out on a lightly floured surface.
• Cut out mini toast shapes with the cookie cutter and place them on the baking tray.

Bake

• Bake the cookies at 170 °C until the edges are lightly golden.
• Let them cool completely on a cooling rack.

Add the brown butter toast crust

• Brush the cooled cookies with the browned butter.
• Dip or sprinkle the tops with the crushed toast crumbs so they look like a toast crust.

Finish with mini butter

• Mix the powdered sugar with the milk to make a thick glaze.
• Pipe or spread a small square of glaze on top of each cookie to look like a pat of butter.