Chef Jean Joho gets to the heart of ingredients. At his high-flying Chicago dining room, Everest, he serves this “plain” dish to complement veal tenderloin, pheasant, or rabbit. It can also be savored alone, as a first course. The cubing step is useful for broken or otherwise imperfect boletes, so that they will cook neatly and evenly. Gently sautéed, the cap pieces turn meltingly soft, while the stems stay slightly springy. The touches of tomato, garlic, and herbs are mere accents: Do not increase the seasoning, or the mellow mushroom’s character will be lost.