Preheat the oven to 220°C.
Blanch chard stalks in boiling water, plunge into iced water, and drain.
Brown shallots in oil over high heat, then discard the oil.
Add 50g butter, bay leaves, thyme, and salt to the shallots and cook for five minutes.
Gradually add stock to shallots until reduced to a thick buttery glaze.
Season steaks and sear them on a griddle, starting with the fat side down.
Cook steaks for four minutes per side, plus two minutes on the narrow edges.
Transfer meat to the oven and roast for six minutes for medium doneness.
Rest the meat for five minutes.
Sauté chard stalks in remaining butter for three minutes, then add leaves to wilt.
Stir in anchovies, capers, and lemon juice and cook for two minutes.
Serve steaks over the chard with the shallots and pan sauce.