Instructions
- Chop red onion and mushrooms.
- On low/medium heat, add olive oil to a pan and soften and color the red onion.
- In a separate pan on low/medium heat, soften and color the mushrooms. Add garlic once softened and mix.
- Remove onion and mushrooms and let cool.
- Lightly wilt spinach in the mushroom pan, then remove and let cool.
- Remove extra fat and silverskin from the flank steak.
- Butterfly the flank steak open along the grain.
- Cover flank steak in plastic wrap and flatten to an even thickness.
- Crumble goat cheese over the flank steak, leaving ~2" empty at the far end.
- Spread red onion, mushrooms, and spinach over the cheese. Season inside with salt and pepper.
- Roll the flank steak tightly and use butcher twine to keep it intact.
- Spread a bit of olive oil on the outside to bind seasoning. Season exterior with salt and pepper.
- Set Traeger (or grill) to 500°F.
- Cook steak directly on the grill for 20 minutes (10 minutes per side).
- Remove and rest for 10 minutes, loosely covered in foil.