Make the Marinade: Grab a medium bowl. Whisk together your olive oil, Worcestershire sauce, and Dijon mustard. Keep whisking until it looks completely smooth and blended.
Marinate the Steak: Place your flank steak in a shallow dish. Pour the marinade all over it, ensuring every inch is coated. Cover the dish securely and refrigerate for at least 1 hour (or overnight).
Sear the Beef: Take the steak out of the fridge and let sit at room temperature for 15 minutes. Heat a nonstick skillet over medium-high heat. Once hot, drop the steak in and leave it completely alone for 4 minutes to build a crust.
Flip and Rest: After 4 minutes, flip the steak over. Cook for another 4 minutes on the other side. Remove the steak from the pan, place it on a clean cutting board, and cover loosely with aluminum foil to rest.
Cool the Pan: Take your skillet completely off the hot burner. Let it cool down for a few minutes so your eggs do not overcook and become rubbery.
Prep the Eggs: Crack your 4 large eggs into a fresh bowl. Add the heavy cream and beat them together until they turn a pale yellow color.
Cook the Eggs: Wipe your cooled skillet clean with a paper towel and put it back on the stove over medium-low heat. Add butter. Once it foams lightly, pour in your eggs. Let sit for a minute, then gently push the cooked eggs to the center, folding for about 2 minutes until soft and fluffy.
Slice and Serve: Uncover the rested steak and slice very thinly against the grain. Divide half of your sliced steak and all the scrambled eggs into two bowls. Fan half an avocado into each bowl, and sprinkle generously with flake salt and cracked black pepper.