In a small bowl or a glass jar with a tight-fitting lid, combine the olive oil, white wine vinegar, chopped parsley, minced garlic, dried oregano, salt, and crushed red pepper flakes.

Stir with a spoon or shake the jar vigorously until the ingredients are well combined and the sauce looks emulsified.

Taste and adjust seasoning with more salt or red pepper flakes if desired. Set aside while you prepare the steak.

Preheat a grill, grill pan, or cast-iron skillet over high heat. Rub the steak with olive oil and season both sides with salt and black pepper.

Grill the steak for about 4 to 5 minutes per side for medium-rare, or until it reaches your desired level of doneness. Remove from heat and let it rest on a cutting board for 5 minutes before slicing against the grain.

Divide the mixed salad greens among four plates. Top with slices of avocado and the rested steak, sliced thinly against the grain.

Drizzle generously with the chimichurri sauce and serve with Meyer lemon wedges on the side for squeezing over the top.