Pat scallops dry with paper towels. Season both flat sides with salt and pepper.
In large skillet, melt butter over medium heat. Add lemon juice, red pepper flakes and minced garlic, and cook for 2 minutes, until garlic is fragrant
NOTE: I use a 12" skillet. If you use a smaller skillet, you will need to reduce the amount of butter. You want enough butter to coat the bottom of the pan, but if you use too much the scallops will steam. It's better to start with a little less, and then add more butter if needed.
Add scallops to skillet. Be sure to leave space between the scallops, or they will steam and not sear. Don't move them for 2-3 minutes! When you see the bottom edge beginning to caramelize, carefully turn scallops over with silicone tongs. Cook on other side for another 2-3 minutes, until bottom is the same caramel color.
Remove scallops from skillet, and drain slightly on paper towels
Add remaining red pepper flakes, drizzle with garlic lemon butter, and top with parsley and lemon zest. Enjoy!