4½ c old-fashioned oats, divided (gluten-free if needed)
2 T cornstarch
1½ t ground cinnamon
1 t baking powder
½ t salt
¾ c granulated sugar
½ c packed light-brown sugar
2 large eggs
2 t pure vanilla extract
½ c white chocolate chips
½ c dried cranberries
½ c chopped cashews
in a small pan, brown one stick of the butter by melting over medium low heat until melted, then cook slowly until the butter begins to turn brown, stirring or whisking occasionally. Be careful not to burn the butter. Set aside to cool to room temperature.
Preheat oven to 350°F.
In a blender, grind 1½ cups oats into a fine powder.
In a bowl, whisk together ground oats, cornstarch, cinnamon, baking powder, and salt.
In a large bowl, with a stand mixer or hand mixer, beat the cooled browned butter, the remaining stick of butter, sugar and brown sugar until light and fluffy.
Beat in the eggs one at a time, then the vanilla.
Reduce mixer speed to low, and gradually add the ground oat mixture, beating until combined.
With a spatula, fold in white chocolate chips, dried cranberries, cashews, and remaining 3 cups oats.
Drop dough in about 1 tablespoon mounds onto a parchment-lined baking sheet, 2 inches apart.
Bake about 12-15 minutes, or until cookies are golden brown at edges.
Let cool on sheet on a wire rack 2 minutes, then transfer to rack to cool completely.