Step 1

For the Popovers: Adjust oven rack to lower-middle position and preheat oven to 400°F. Place two muffin tins in the oven to preheat; note that you will be using about 18 of the tins.

Step 2

Combine eggs, flour, salt, pepper, cayenne, thyme, milk, and cheese in a blender using a low-speed setting. Do not over mix. Remove tins from oven, quickly spray with cooking spray and pour batter into tins, filling 18 wells halfway. Place in oven and bake until puffed-up and golden brown, 20 to 25 minutes. Remove from oven and cool on a wire rack.

Step 3

For the Beef: While popovers bake, season roast with salt and pepper. Heat 2 tablespoons olive oil in a Dutch oven or heavy-bottomed, oven-safe roasting pan until shimmering. Add roast and cook, turning occasionally, until wall-browned on all sides, about 8 minutes total. Transfer meat to large platter and set aside.

Step 4

Add thyme, sage, parsley, oregano, paprika, garlic, mustard, and remaining 1/2 tablespoon olive oil to a blender or food processor. Season with a pinch of salt and pepper and pulse until it forms a paste. Generously rub herb mixture on meat. Return roast to Dutch oven or roasting pan. When popovers are done, reduce oven to 350°F. Transfer Dutch oven or roasting pan to oven and roast until an instant-read thermometer inserted in the thickest part registers 125°F for medium rare or 135°F for medium, about one hour. Remove from oven and transfer to a cutting board. Tent with foil and allow to rest 10 to 15 minutes.

Step 5

For the Sauce: While the roast is resting, combine sour cream, horseradish, Worcestershire sauce, and lemon juice in a small bowl. Season with salt and pepper to taste. Return popovers to oven to reheat for 5 minutes.

Step 6

Carve meat, arrange slices on a platter and serve immediately with horseradish cream and popovers.