The Beartooth Recipe

Cook onions low and slow

Heat a medium nonstick skillet over medium-low heat. Add butter and olive oil. Once butter is melted, add thinly sliced yellow onion and spread into an even layer.

Sprinkle kosher salt over the onions to draw out moisture. Cook, stirring every 3–4 minutes, until onions are deeply golden and very soft, about 20–25 minutes. Reduce heat if they begin to brown too quickly.

Stir in brown sugar and balsamic vinegar, increase heat to medium, and cook 2–3 minutes until jammy and slightly reduced. Taste and season with freshly ground black pepper. Remove from heat and set aside.

In a small bowl, whisk together mayonnaise, prepared horseradish, Dijon mustard, lemon juice, garlic powder, and salt until smooth and well combined. Taste and adjust horseradish or salt to preference. Refrigerate until assembly.

If using a cold deli roast beef and you prefer it warm, preheat a skillet over medium-high. Briefly warm roast beef in batches for 30–45 seconds per side just to heat through; do not overcook or dry out the meat. Alternatively, you can steam the slices by covering them in a skillet with a splash of water for 1 minute.

Split the hero roll lengthwise, leaving a hinge if desired. Lightly toast cut sides in a skillet or oven (350°F / 175°C) for 3–5 minutes until just golden — this prevents sogginess and adds texture.

Spread a generous layer (about half of the horseradish aioli) on the bottom half of the roll and a thin swipe on the top half.

Layer the warmed roast beef evenly on the bottom half of the roll, tucking slices so they create a tall, even mound (use all roast beef).

Drape provolone slices over the warm roast beef so they soften and begin to melt slightly. If you prefer fully melted cheese, place the open sandwich under a broiler for 30–45 seconds, watching carefully.

Spoon the onion jam over the cheese and beef, distributing it evenly. Add sliced pepperoncini across the sandwich for tang and heat. Add optional baby arugula and pickle slices if using.

Close the sandwich, press gently, and cut in half on a diagonal. Serve immediately while the beef is warm and the cheese is melty.