Preheat oven to 425 F.
Season steak w/ S&P.
Heat a large oven proof saute pan over med-high heat. Add steak and sear both sides ~4 mins until deep brown.
Transfer steak to oven and cook another 4-8 mins or to desired doneness. Remove steak from oven and allow to rest for 10 minutes.
Meanwhile, if blackberries are large, slice in half.
Layer salad in a large bowl: ½ of arugula + ½ pint blackberries + 1/4c almond slices. Repeat layers.
Cut steak against the grain into thin slices. Serve on top of salad tossed w/ balsamic dressing.