Add the room temperature butter to a mixing bowl or bowl of a stand mixer.
Add in the white and brown sugar and cream together with an electric mixer for about 30 seconds.
Add in the egg and vanilla and beat together until combined.
Add in the flour, cornstarch, baking soda and salt. Mix together until combined.
Fold in the shredded coconut and white chocolate chips.
Scoop the dough using a 2 tablespoon scoop and place on a baking sheet lined with parchment paper.
Place in the fridge to set for 1 hour. Don't skip this step or the cookies will spread prematurely!
Toward the end of the hour, preheat the oven to 350 Fahrenheit.
Split the cookies between two baking sheets - I suggest just 6 cookies per sheet to ensure they have enough room for spreading.
Bake for 13-16 minutes or until the edges are just golden brown. They will continue to firm as they cool.
Use a round cookie cutter to swivel around the edges to create perfect circles.
Let cool for about 15 minutes, then transfer to a wire rack to finish cooling, then enjoy!