This is a lazy bum's approach to Bercy Butter. I skipped the traditional wine and stock because reducing liquid is too much for my patience on a workday. Cooking shallots in the pan that you seared steak in will give it a good amount of beefy flavor. Regular olive oil/butter works too. When it's topped on a steak the difference won't be too noticeable. What you're really looking for is the aromatic shallots and parsley.
1 stick butter, softened* (see shortcut for quick softening)
1 shallot, minced
1/4 cup parsley, finely chopped
1 tbsp oil/butter/tallow, for frying the shallots
Fry minced shallot on medium heat until softened and slightly caramelized. You can cook this in the pan that you just cooked steak in.
To soften butter quickly, microwave a whole stick with wrapping paper on, for 5~7 seconds, rotate the stick 90 degrees, repeat 4 times for all 4 sides. This will heat the butter evenly. butter should be just softened and not liquid.
Beat softened butter, fold in shallots and chopped parsley. Roll in parchment paper. Refrigerate to harden. Slice and top it on your steak. Enjoy!