01 - Pat the steak cubes dry using paper towels. Season them evenly with salt and black pepper.
02 - Heat olive oil in a large skillet over high heat.
03 - Place steak cubes in a single layer in the skillet. Sear without moving for 2 to 3 minutes, then flip and cook for another 2 to 3 minutes until the steak is browned to desired doneness. Avoid overcrowding by cooking in batches if needed.
04 - Lower heat to medium-low. Add butter and minced garlic to the skillet. Stir continuously for 1 to 2 minutes until butter melts and garlic becomes fragrant, fully coating the steak cubes.
05 - Sprinkle chopped parsley and optional crushed red pepper flakes over the steak. Toss gently to combine and serve immediately.