|Prep Time||15 minutes|
|Cook Time||1 hour|
- 1 (3.5 pounds) beef tenderloin tied with kitchen twine at 2-inch intervals
- Coarse salt
- Freshly ground pepper
- 4 tablespoons unsalted butter room temperature
- 3 tablespoons grainy mustard
- 1 tablespoon Dijon mustard
- 2 small acorn squash seeded and cut into 1-inch wedges
- 1 head (about 3 cups) frisee torn
- 1/2 cup fresh flat-leaf parsley
- 1 tablespoon sherry vinegar
- 2 tablespoons extra virgin olive oil
- Remove beef from refrigerator and let stand at room temperature for 1 hour; pat dry.
- Preheat oven to 425 degrees F.
- Season beef with salt and pepper.
- Stir together 3 tablespoons butter and both mustards. Spread mixture over tenderloin to cover.
- Place beef on a rimmed baking sheet. Arrange squash around beef and brush squash with remaining butter; season with salt and pepper.
- Roast until an instant read thermometer inserted into center of the beef reaches 130 degrees F (medium rare), about 30-40 minutes depending on thickness of the cut. Flip squash half way through cooking.
- When cooked through, remove baking sheet and let beef rest 15 minutes before slicing.
- Toss frisee, parsley, and squash with vinegar and oil and season with salt and pepper.
- Serve tenderloin with greens and squash.