A few notes from someone who used to bake professionally:
—Butter that is colder than room temp fine. No need to have rock-cold cubes.
—Use a spring-form COOKIE SCOOP to ball out the dough BEFORE CHILLING. Line the balls together on whatever sheet tray or plate that will fit in your fridge. I’m sure that will save a lot of novice bakers some stress. You can do this (rather should do this :) for all your drop cookie dough. I do! :) Very efficient pro tip.
—One hour of chilling time is more than fine. Longer is totally fine. Yes you can freeze the dough balls and de-frost for later baking.
—Since I made it easy on myself and portioned the dough already, just place the cold dough balls on your parchment’d baking sheet while the oven reaches temp.
—I used three slices of almond on top pointed in the center like a star-ish shape. that’s just preference of course.
—painting the egg wash on the sides is also important.
—to get some semblance of golden brown edges, I had to bake for a min