Heat a heavy skillet (cast-iron preferred) over medium-high heat until very hot. Add 1 tablespoon olive oil and swirl to coat. Place the filet in the pan and sear without moving for 2–3 minutes, until a deep brown crust forms.

Flip and baste

Flip the filet and add 1 tablespoon butter, the smashed garlic cloves, and thyme sprigs to the pan. Tilt the pan slightly and use a spoon to baste the steak with the melted butter and pan juices continuously for 1.5–3 minutes, until the desired doneness (see note). For medium-rare aim for an internal temperature of 125–130°F (52–54°C).

Rest

Transfer the filet to a cutting board and tent loosely with foil. Rest for 6–8 minutes to allow juices to redistribute while you make the pan sauce.

Red Wine Pan Sauce

Sauté shallot

With the skillet still over medium heat (use the drippings but discard the garlic and thyme if they’ve burned), add the minced shallot. If the pan is dry, add 1–2 teaspoons olive oil. Sauté 1–2 minutes until softened and translucent, not browned.

Deglaze

Pour in 3 tablespoons dry red wine to deglaze the pan, scraping up browned bits with a wooden spoon. Cook 1–2 minutes until the wine reduces by about half.

Add stock and reduce

Add 1 cup beef stock and bring to a simmer. Reduce gently until the sauce thickens slightly and coats the back of a spoon, about 6–8 minutes.

Finish with mustard and butter

Whisk in 1 teaspoon Dijon mustard. Remove the pan from heat and swirl in 1 tablespoon cold cubed butter a piece at a time to emulsify and glossy the sauce. Taste and adjust seasoning with a pinch of salt and pepper.

Add herbs

Stir in the chopped fresh parsley just before serving.

Plating & Garnish

Slice the rested filet into 1–1.5 inch medallions (or serve whole). Spoon the red wine pan sauce over or alongside the meat. Garnish with microgreens or chopped parsley and a lemon wedge if desired.

Serve immediately while warm.