Jul 09 2026
RestaurantsBoard & Brew - Del MarRoast Beef Spicy Recipe

Roast Beef Spicy Recipe

Time4h
Serves2

Slow-roasted beef, melted Swiss cheese, red onions, jalapeño peppers, dijon mustard, & mayo served hot on a toasted French baguette with a side of au jus

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Ingredients

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FROM THE GRILL

Method

FROM THE GRILL

  1. 1

    Prepare the beef rub

    In a small bowl, whisk together garlic powder, onion powder, salt, and black pepper. Rub the beef roast all over with 2 tablespoons olive oil and press the spice mix onto the surface to coat evenly.

  2. 2

    Roast the beef

    Place the beef roast on a rack in a shallow roasting pan. Roast in a preheated oven at 250°F (120°C) until the internal temperature reaches 135-140°F (57-60°C) for medium-rare, about 3 to 3.5 hours. Remove and tent loosely with foil.

  3. 3

    Rest and slice

    Let the roast rest for at least 20 minutes, then slice thinly against the grain into even slices suitable for the sandwich.

  4. 4

    Caramelize red onions

    In a skillet, melt 2 tablespoons butter over medium heat. Add the sliced red onion and cook slowly, stirring occasionally, until deeply browned and caramelized, about 20–25 minutes. Season with a pinch of salt.

  5. 5

    Flame-soften jalapeño

    In the same skillet, add jalapeño slices and cook 1–2 minutes to soften and release a light heat. Remove from heat.

  6. 6

    Make mayo-Dijon spread

    In a small bowl, whisk together mayonnaise and Dijon mustard until smooth. Set aside.

  7. 7

    Toast the baguette

    Slice the baguette lengthwise. Brush the cut sides with melted butter and toast on a griddle or under the broiler until lightly golden.

  8. 8

    Assemble the sandwich

    Spread the mayo-Dijon spread on the inside of both halves. Layer the sliced beef on the bottom half, then top with Swiss cheese.

  9. 9

    Finish with onions and heat

    Pile the caramelized onions and jalapeño slices over the cheese. Close the sandwich and press briefly to melt the cheese.

  10. 10

    Serve with au jus

    Cut the sandwich into portions and serve hot with a side of warm au jus for dipping.

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