1. Make the Sauces (Both Should Chill)

Horseradish Sauce:
Combine sour cream, mayo, apple cider vinegar, black pepper, granulated garlic, and prepared horseradish. Mix thoroughly and chill.

Blue Cheese Spread:
Combine blue cheese crumbles, sour cream, mayo, and black pepper. Mix thoroughly and chill.

2. Preheat the Grill & Griddle
Fire up your Z-Grills and set the temperature to 400°F-450F

Place your griddle in the center of the grill.

Allow it to reach ~360°F before cooking.

3. Prep & Toast the Bread

Once the griddle hits about 360°F:

Toast your bread to get a light, crisp surface.(ADD YOUR FAVORITE TOPPINGS TO THE BREAD BEFORE TOASTING) I went with black pepper, granulated garlic, and olive oil!

Remove and set aside.

4. Cook the Onions

Add your thick-sliced red onions to the griddle.

Cook about 1 minute per side until you get color.

Flip, finish, and remove from the griddle.

By now, your griddle should be climbing toward 400°F or even 450°F.

5. Salt-Brine & Cook the Steaks

Salt Brine:

About 1/8 teaspoon kosher salt per steak side, covering both sides and the edges.

Let sit 1 hour on the board before cooking.

Cook:

Once the griddle is 400-450°F, lay the steaks down.

Close the hood and cook 2 minutes.

Quarter-turn the steaks and cook another 2 minutes.

Flip at the 4-minute mark and cook to desired temp (medium rare recommended).

Remove and let the steaks rest.

6. Build the Sandwiches

A. Ultimate Horseradish Steak Sandwich
Spread horseradish sauce on the bottom slice of toasted bread.

Add a layer of peppery watercress.

Slice the rested steak and lay it gracefully across the greens.

Add another drizzle of horseradish sauce.

Top with the griddled red onions.

Crown with the top slice of bread.

B. Ultimate Black & Blue Steak Sandwich
Spread the blue cheese dressing on the bottom slice of bread.

Add watercress.

Lay sliced steak gracefully across the greens.

Add a generous amount of extra crumbled blue cheese (not the dressing).

Top with the griddled red onions.

Crown with the top slice of bread.

7. Finish

Cut both sandwiches in half.

Serve immediately and enjoy the ultimate steak sandwich experience.