Recipe: (Watch for assembly instructions)!

1 cup butter melted

1 cup light brown sugar tightly packed

½ cup sugar

2 large eggs + 1 large egg yolk

1 ½ teaspoons vanilla extract

1 ¼ cup all-purpose flour

2 teaspoons cornstarch

½ teaspoon baking powder

¼–½ teaspoon ground cinnamon

3 cups old fashioned rolled oats

1 ½ cups chocolate chips optional, I did a mix of semisweet chocolate chips, milk chocolate chips, and butterscotch chips