**Make sure all ingredients are at room temperature.**

Preheat oven to 355F (180C). If you have a fan-forced oven, set to 320F (160C).

In the bowl of a stand mixer, on medium speed, cream together the butter, brown sugar and granulated sugar.

Mix in 1/2 teaspoon blue liquid food dye. Scoop half the cookie dough into a glass microwaveable bowl and microwave on 100% power for 20 seconds, stirring half way. The colour of the dough should have darkened. If it hasn't, heat for a further 10 seconds. 

Mix back into the remaining cookie dough. On medium speed, add the eggs and the remaining food dye and mix until combined.

With the mixer still running, add the flour. If needed, turn off the mixer and scrape down the sides and bottom of the bowl with a rubber spatula to make sure the flour mixes in. Once the cookie dough is formed, pour in 3/4 cup chocolate chips and mix until combined.

Use an ice cream scoop (or the equivalent of 2 heaped tablespoons) to scoop cookie dough onto a baking tray lined with parchment/baking paper, leaving 3" (7.5cm) between cookie dough balls. Do not press the cookie dough down, they will flatten as they heat.

Press the remaining chocolate chips onto the top of each cookie dough ball before placing tray in the oven. Bake for 20 minutes.

Remove the tray from the oven and let them cool for 5 minutes before transferring cookies to a cooling rack for another 5 minutes.