Cream the butter and sugars

• In a large bowl, cream together the softened butter, brown sugar and granulated sugar until light and fluffy.

Add the wet ingredients

• Add the egg, egg yolk and vanilla and mix until fully combined.

Fold in the dry ingredients

• Fold in the flour, cornstarch, baking soda and salt until just combined.
• Fold in the white chocolate chips.

Shape the cookies

• Scoop the cookie dough, flatten each portion, stuff a piece of white chocolate inside and shape into a cone shape.
• Place onto a parchment-lined baking sheet, leaving plenty of space between each cookie.

Bake

• Bake at 375°F (190°C) until the edges are lightly golden but the centers still look slightly underbaked.

Shape while warm

• While the cookies are still warm, use a cookie cutter or a cup to gently shape them into perfect circles.
• Allow the cookies to cool on the baking sheet before transferring.

Optional white chocolate base

• Pour melted white chocolate onto a parchment-lined cookie sheet and place a cookie on top.
• Let cool before serving; depending on the brand, the cookies may take longer to set with the chocolate underneath.