Preheat your oven to 350° and line 2 cookie pans with parchment paper.
In a separate bowl weigh or measure the flour, baking soda, baking powder, and salt. Take a whisk and run it through the dry ingredients to blend. Set the bowl aside.
Weigh out or measure the light brown and white sugars and add them to the bowl of your hand or stand mixer. Add the butter and beat till the sugar is blended with the sugars. It took about 2 to 3 minutes at the number 6 (medium-high) setting on my KitchenAid stand mixer.
Add the milk, egg, and the orange juice to the butter-sugar mixture and turn the mixer to medium-high and mix till it looks smooth.
Turn your mixer down to low and gradually add the bowl with the flour, baking soda, baking powder and salt to the wet mixture. Blend till smooth. Take the bowl off the stand mixer and stir in the chopped cranberries and chopped walnuts.
I use a OXO Good Grips Cookie Scoop, Medium to make 12 scoops on the parchment paper. Bake at 350° for 14-16 minutes. Leave them on the pan for a minute or two before moving them to the cooling rack.
Put the butter into a pan and heat over medium-low till the butter is a light brown, and has a nutty smell. This takes at least 5 minutes after the butter melts and starts to bubble. Stir once in a while. Let the brown butter cool for a minute or two in a small bowl.
Add brown butter, powdered sugar, and vanilla extract to the bowl of your mixer and blend on medium speed. For my frosting I added only 2 tablespoons of hot water but if you like your frosting a little thinner just add little more water. You can always add more water but you cannot take it out if you add too much. So add a little at a time.