Keep beef chilled until ready to work. Trim any fat or sinew and use a very sharp knife to finely dice the beef into small, even 1/8–1/4-inch pieces. Return to a chilled bowl.

Add minced shallot, cornichons, chopped capers and chopped parsley to the diced beef. Gently fold to combine.

Whisk together 1 tsp Dijon mustard, 2 tbsp sherry vinaigrette, 1 tsp olive oil, 1/2 tsp sea salt and 1/4 tsp freshly ground black pepper in a small bowl, then pour over the beef mixture. Toss gently to coat. Taste and adjust seasoning — add a little more vinaigrette or salt if needed. Keep chilled while finishing other components.

Sherry Vinaigrette

Make the vinaigrette

In a small bowl or jar combine 1 tbsp sherry vinegar, 1/2 tsp white wine vinegar, 1 tbsp minced shallot, 1/2 tsp Dijon mustard and 1/2 tsp honey. Whisk to combine. Slowly stream in 3 tbsp extra-virgin olive oil while whisking until emulsified. Season with 1/4 tsp sea salt and 1/8 tsp freshly ground black pepper. Taste and adjust acidity or sweetness as desired. Set aside.

Grilled Sourdough & Finishes

Heat a grill pan or skillet over medium-high heat. Lightly butter one side of each sourdough slice. Place buttered side down in the hot pan and grill until golden and crisp, about 1–2 minutes. Flip and grill the other side very briefly just to warm, 30–45 seconds. Remove from pan.

While warm, rub the grilled sides with the cut garlic clove to impart a subtle garlic note. Keep warm.

If serving raw yolks: carefully separate yolks from whites and keep yolks whole in a small bowl or ring to serve. For a safer alternative, you can briefly sous-vide yolks at 135°F (57°C) for 45 minutes to thicken slightly; otherwise serve raw only if eggs are very fresh and from a trusted source.

To assemble, divide tartare into four portions (approximately 2 oz beef per serving). Use a ring mold atop each grilled sourdough slice or mound the tartare on the plate beside the toast.

Top each portion with a few thin shavings of manchego and a small spoonful of any remaining vinaigrette. Gently place one egg yolk on top of each tartare mound (or serve yolk on the side). Garnish with microgreens or baby arugula if using, and finish with a pinch of flaky sea salt and a crack of black pepper.

Serve immediately so the toast remains crisp and the yolk can be broken over the tartare at the table.