For the Half-and-Half Short Ribs:
Heat oven to 325ºF.
Heat oil, 3 turns of the pan, in a large Dutch oven over medium-high heat. When oil smokes, add 3 ribs at a time and deeply brown on all sides before removing to a plate. When all of the meat has been browned, add onions, garlic, carrots, celery, bay, herbs and juniper berries (if using) to the pot. Season with salt and pepper and partially cover. Cook vegetables 8-10 minutes, stirring occasionally, then deglaze the pan with balsamic vinegar. Add port and wine, and reduce by half. Add stock and settle meat back into pot bone-side up. Cover and roast 2 1/2-3 hours, until very tender.
Cool ribs to remove fat. (Making them a full day-ahead of time is best.)