Making the Cookies

• In a large bowl, whisk together the flour, cornstarch, baking soda and salt.
• Pour the melted butter into a medium-sized bowl. Add in brown and granulated sugar, and whisk vigorously, until no sugar lumps remain. Whisk in the egg, the yolk, and add the vanilla extract.
• Add the wet ingredients to the dry ones and mix together with a spatula. Fold in the chopped white chocolate. Then carefully fold in the fresh or frozen raspberries.
• Roll the dough into balls, place onto a baking sheet covered with parchment paper, and cover with plastic wrap. Chill in the refrigerator for 30 minutes, then allow the dough to soften at room temperature for about 5 minutes before using it.
• Preheat the oven to 325°F (160°C) and line two large cookie sheets with parchment paper.
• Place the balls onto the prepared baking sheet, spacing them from 2-inch (5 cm) apart. Gently flatten the top of each cookie dough with your hand.
• Bake each batch for about 10 to 12 minutes, until the edges are set. Allow the cookies to rest on the pan 5 minutes, then remove to a wire rack to cool completely.
• If the cookies haven’t flattened as much as you’d like, bang the pan on the counter once or twice and use a large round cutter to 'scoot' the cookies into a perfectly round shape, if desired.