Flat Iron Filet

Mustard-Grilled Steak Panini with Giardiniera

steak panini with mustard

Flat Iron Filet

Mustard-Grilled Steak Panini with Giardiniera

Prep Time: 5 minutes
Cook Time: 20 minutes
Servings: 4

This delicious recipe pairs grilled Natural Angus flat iron steak with tangy and spicy pickled vegetables, creating a bright and unique sandwich that is perfect for lunch or dinner.


1 1/2 pounds Aspen Ridge® Natural Angus Beef flat iron filet

1 teaspoon coarse salt

1/2 teaspoon freshly ground black pepper

3 Tablespoons Dijon mustard

4 panini buns, split

2 Tablespoons extra-virgin olive oil

1 cup jarred Giardiniera, drained and coarsely chopped

1 cup grated Fontina cheese


  1. Preheat a grill to high and oil the grates. Remove steak from the fridge and let stand at room temperature 30 minutes.
  2. Sprinkle the steak with the salt and pepper and spread the Dijon on both sides. Grill about 5-8 minutes per side or until steak registers 130°F for medium-rare. Transfer to a cutting board and let rest 10 minutes.
  3. While steak is resting, brush the insides of the panini rolls with the olive oil and toast the insides on the grill. Thinly slice the steak and pile onto rolls, topped with Giardiniera and cheese. Cover with the tops of the rolls, pressing down and place back on the grill. Place a heavy skillet on top and grill another minute or two until toasted on the bottom. Flip the panini and grill another minute or until nicely browned and cheese has melted. Cut in half and serve.