Preheat the oven to 375°F. Arrange the baguette slices on a baking sheet in a single layer and brush each slice lightly with softened butter. Bake for 8-10 minutes or until golden and crisp. Remove from the oven and set aside to cool.
Season the ribeye steak evenly on both sides with kosher salt and freshly ground black pepper.
Heat olive oil in a large skillet over medium-high heat. Sear the steak for 3-4 minutes on each side, or until a golden-brown crust forms and the internal temperature reaches 130°F for medium-rare. Transfer the steak to a cutting board and let it rest for 5 minutes.
Slice the rested steak thinly against the grain into bite-sized pieces.
Top each toasted baguette slice with a piece of steak, followed by a sprinkle of crumbled blue cheese.
In a small bowl, mix minced garlic and finely chopped parsley. Sprinkle this mixture over the crostini for added flavor and garnish. Serve immediately.
Notes
Perfect appetizer ready in 35 minutes for any occasion.