Preheat your oven to 350°.
In the bowl of a stand mixer, cream together the butter and sugar for 1 minute.
Scrape the sides of the bowl and add in the eggs, lemon emulsion and canola oil. Mix until well combined.
Add in the flour and baking powder. Mix until a soft dough forms.
Add the yellow food coloring a few drops at a time until you have a deep yellow color. The cookies will get lighter as they bake.
Lastly, mix in the white chocolate chips.
Scoop the cookie dough out in a heaping 1/3 cup portions. Roll into a ball. Break the ball in half and then smash the two half back together, leaving the rough edges up. This will give the cookie top some good texture.
The cookies will spread and flatten a bit as they bake, so keep them fairly tall. Repeat with the remaining dough.
Arrange on a parchment paper or silicone baking mat covered pan. Place 6 cookies on each tray.
In a small bowl, combine the powdered sugar and corn starch.
Spoon a generous amount of powdered sugar onto the top of each cookie.
Bake at 350° for 14-16 minutes. The cookies will spread slightly and puff up in the center. That is when you know it's time to take them out of the oven.
Allow the cookies to cool on the pan for 20 minutes before serving.
Serve warm and enjoy!