Stir wine, cornstarch, and one tablespoon soy sauce in a medium bowl; set marinade aside.
Stir vinegar, hoisin sauce, sugar, sesame oil, and remaining two teaspoons soy sauce in a small bowl; set sauce aside.
Remove leaves and cut cauliflower into medium florets. Trim woody end of stalk and discard, then cut stalk into 1.25 centimeter thick pieces. Heat one tablespoon vegetable oil in a wok or large cast-iron skillet over medium-high. Cook cauliflower, tossing occasionally, until browned in places and beginning to soften, seven to nine minutes. Give reserved marinade a stir to reincorporate cornstarch and add cauliflower to bowl; toss to coat. Toss occasionally while you cook the bacon.
Reduce heat to medium. Cook bacon and remaining one tablespoon vegetable oil in wok, stirring often, until bacon is browned and crisp, about five minutes. Add dried chiles and peppercorns and cook, tossing, just until fragrant (be careful not to burn), about 30 seconds. Transfer bacon, chiles, and peppercorns to a plate, leaving bacon drippings behind.
Return cauliflower to wok with a slotted spoon; discard excess marinade. Cook cauliflower, tossing occasionally, until charred in spots and crisp-tender (short of scorching it, don’t worry about letting it go pretty dark), eight to ten minutes. Add scallion whites, serrano chile, ginger, garlic, and peanuts and cook, tossing often, until sauce is fragrant and cauliflower is tender, about two minutes. Add bacon mixture and cook, tossing, just until sauce coats cauliflower, about one minute; season with salt.
Transfer to a serving dish and top with scallion greens. Serve with rice alongside.