1. Preheat your grill to medium-high heat. Season the beef tenderloin with salt and pepper. Grill until medium-rare, about 4–5 minutes per side depending on thickness. Let it rest 10 minutes before slicing thinly.

2. Preheat your oven to 375°F (190°C). Slice the baguette into 1/2-inch rounds. Brush with olive oil and bake until golden and crisp, about 8–10 minutes.

3. In a small saucepan, combine shallots, vinegar, and half the tarragon. Simmer until reduced by half. Let cool slightly.

4. In a double boiler, whisk egg yolks and the vinegar reduction over low heat. Slowly whisk in melted butter until the sauce thickens. Add lemon juice and remaining tarragon. Strain if needed for smoothness.

5. Top each toasted baguette slice with a piece of grilled tenderloin. Spoon warm Béarnaise sauce on top. Garnish with fresh tarragon or cracked pepper. Serve immediately.