Place the beef in the freezer for 15–20 minutes to firm slightly — this makes it easier to dice finely. Trim away any silver skin and excess fat; pat dry with paper towels.

Dice the beef

Using a sharp knife, cut the chilled beef into 1/8–1/4-inch dice. Aim for uniform small pieces. Transfer the diced beef to a chilled bowl and keep refrigerated until ready to season.

Prepare aromatics and condiments

Finely mince the shallot, chop the capers, dice the cornichons, and chop the parsley. Place all these prepared ingredients in a small bowl and mix with the Dijon, Worcestershire, lemon juice, olive oil, salt and pepper to form a seasoning mixture.

Combine with egg yolks

Add the two chilled egg yolks to the seasoning mixture and whisk briefly to combine. Fold the seasoning mixture into the diced beef gently but thoroughly, tasting and adjusting salt and pepper. Keep the tartare chilled until assembly.

Crisp Garnishes & Assembly

Toast brioche rounds (if not pre-toasted)

Preheat oven to 350°F (175°C). Place brioche rounds or crostini on a baking sheet and toast for 5–7 minutes until golden and crisp. Allow to cool slightly.

Portion the tartare

Using a small spoon or a 1-tablespoon cookie scoop, portion about 1 tablespoon of tartare onto each brioche round (roughly 12 portions). Gently mound the tartare to create a neat mini tower.

Garnish and finish

Top each mini tartare with a thin slice of cornichon and a small sprig of microgreens or parsley. Finish with a light crack of freshly ground black pepper and, if desired, a tiny drizzle (a few drops) of extra-virgin olive oil.

Serve

Arrange the mini tartars on a platter and serve immediately while the brioche remains crisp and the beef is chilled.