Combine the soy sauce, soy oil, balsamic vinegar, mirin, black peppercorns, sugar and salt in a blender and blend well. Mix with the garlic, thyme and rosemary.
Pour the marinade over the steaks and refrigerate for at least 6 hours.
For the cherry sauce:
Gently saute the shallots in half the butter in a heavy-bottomed pot until soft and translucent. Add the mustard and cook for one minute. Hold the pan away from the flame, add the brandy, and then return to the flame to ignite and flambe the shallots. When the flame dies down, add the cherries with their rehydrating liquid and the veal stock. Bring to a boil and simmer for 10 minutes, and then stir in the remaining butter. Finish with the tarragon and lots of freshly cracked pepper.
Heat a cast-iron skillet over medium-high heat and add some oil. Pat the steaks dry with a paper towel and sprinkle with salt and pepper. Saute until nicely browned all around, about 7 minutes for medium rare. Remove and let rest for at least 2 minutes on a paper towel. Place the steaks on a large plate and ladle the sauce directly on top. Serve immediately.