In a medium-sized saucepan or saute pan, melt the butter over medium heat. Stir constantly with a spatula. The butter will foam while cooking, then it will subside slightly before the butter is fully browned. Continue to cook for 5 to 10 minutes, or until the butter smells nutty and the milk solids at the bottom of the pan turn golden brown. Be careful to not burn the butter, as the browning happens quickly. Immediately, remove the browned butter from the heat to prevent burning. Allow the butter to cool to room temperature, no need to solidify, before using in the recipe.

Preheat the oven to 350°F. Line a baking sheet with a silpat liner or parchment paper. Set aside.

In a large bowl, mix together the browned butter, brown sugar and white sugar until smooth with a wooden spoon or spatula.

Stir in the eggs and vanilla extract until combined.

Add the flour, cornstarch, and baking soda. Gently mix until all the flour is incorporated. Don't over-mix the cookie batter.

Using a small cookie dough scoop, drop 1 ½ inch balls of dough on the prepared baking sheet.

Bake for 9-10 minutes, or until the edges start to turn a golden brown and the middle is puffed and slightly pale. Don’t over bake!

Cool the cookies for 10 minutes (or until set) on the baking sheet (see notes for extra tips!). After 10 minutes, remove the cookies to the wire racks to cool completely.

Store at room temperature in an airtight container for up to 1 week or the freezer for up to 3 months.