1.5 pounds beef tenderloin cut into twelve 1/4-to- 1/2-inch-thick pieces
1.5 teaspoons dijon mustard
0.8 cup horseradish drained
12 servings kosher salt and pepper freshly ground
0.3 cup mayonnaise
12 servings onion rings for topping
12 slider buns split
2 tablespoons cup heavy whipping cream sour
0.5 teaspoon sugar
4 tablespoons butter unsalted
Equipment
bowl
frying pan
oven
Directions
Mix the horseradish, mayonnaise, sour cream, mustard, sugar, 3/4 teaspoon salt and 1/4 teaspoon pepper in a bowl. Cover and chill at least 2 hours.
Make the sliders: Melt 1 tablespoon butter in a large nonstick skillet over medium-high heat.
Add the bun bottoms, cut-side down, and cook until golden; set aside. Melt 1 more tablespoon butter in the skillet and toast the bun tops until golden; set aside.
Season the beef generously with salt and pepper.
Heat the remaining 2 tablespoons butter in a large cast-iron skillet over medium-high heat. Working in batches, add the beef and cook until browned but still pink in the center, about 2 minutes per side. (You can also cook the tenderloin in one piece: Brown on all sides, then roast in a 425 degrees F oven, 10 to 15 minutes.
Let rest, then slice into 12 pieces.)
Assemble the sliders: Put a slice of beef on each bun bottom. Top each with a generous spoonful of the horseradish cream, some onion rings and a bun top.
