Crostini with Beef & Horseradish Cream

• 1/2 lb. beef tenderloin (about a 1-1/2-inch steak)
• Kosher salt and freshly ground black pepper
• 1/4 cup crème fraîche (or sour cream)
• 2 to 3 tsp. prepared horseradish
• 1 recipe Crostini
• 16 pale, inner pieces of frisée (curly endive), washed and dried

Heat a small, heavy skillet over high heat for 1 minute. Season the beef with 1/4 tsp. salt and some pepper. Turn the exhaust fan to high and sear the beef, flipping after 3 minutes, and then cook, flipping every couple of minutes until it’s done to your liking, about 10 minutes total for medium rare. Transfer to a cutting board, let rest for 5 minutes, and then slice the beef thinly.

Mix the crème fraîche and horseradish in a small bowl; season with 1/4 tsp. salt and a few grinds of pepper.

To assemble, top the crostini with a slice of beef, a dollop of the crème fraîche, and a small piece of frisée and serve.