Preheat oven to 350 degrees F. Line baking sheet with parchment paper.
In small pot, add butter over medium heat.
Stirring frequently to constantly, melt butter and continue to cook until brown specks form in the butter. This typically takes around 10 minutes. Once it starts to brown, remove from heat immediately to prevent burning.
Let cool slightly for 10 minutes.
While cooling, in medium bowl combine flour, oats, baking soda, salt, and spices and mix to combine.
In large bowl with electric mixer, beat together brown butter, sugar, and brown sugar until well combined.
Add eggs, one at a time, beating until combined.
Add molasses and vanilla, beating to combine.
Slowly add in flour/oat mixture, beating until well combined. Scrape down the edges of the bowl as needed.
Scoop into ~2 tablespoon worth of cookie dough balls, and place on prepared cookie sheet.
Roll into balls and roll in sugar.
Bake in preheated oven for 9-11 minutes, until edges are slightly golden.
Let cool completely.
Enjoy!