Cut your (1 cup unsalted) butter into smaller chunks. Place in a pot on the stove over medium-low heat (You can use medium heat, but be careful not to burn your butter!)
Stir your butter so it melts consistently. Eventually, you will see that the butter starts to foam and froth on the top. Keep stirring.
Then, you will see flecks of solidified milk fat floating around in your butter. Keep stirring.
Finally, the butter will start to foam again, but with less vigor than before. Keep stirring and checking on the color of your butter.
Your butter is browned when it achieves an amber color and you can see little brown specks on the bottom. The specks are kind of hard to see due to the foam on the top, you have to move the foam to be able to see.
Remove the pot from the heat and let the butter cool a little.
Place browned butter in a bowl and let chill in the fridge until it is solid again, about one hour.