Aquavit chef Emma Bengtsson grew up eating this stuffed cabbage, lovingly made by her mother and grandmother. Stuffed cabbage is very forgiving; you can make it the day before, store in the fridge, then simply reheat and serve. Weeknight dinner rush: solved!
Cabbage and rice: Cut out the core of the cabbage with a sharp knife. Remove the large, bitter outer leaves from the cabbage and discard. Carefully pull off the remaining larger leaves (about 10 of them), keeping them whole and as undamaged as possible. (Reserve the remaining cabbage for another use, such as Hugh Acheson's Apple-Cabbage Slaw). Meanwhile, add rice, milk, and a pinch of salt to a medium saucepan over medium-low heat. Bring to a low simmer and cook uncovered until the grains absorb the milk, stirring occasionally, 10-20 minutes.
Onion and potatoes: Melt 1 tablespoon butter in a skillet over medium-high heat; sauté onions until soft, stirring occasionally, 4-5 minutes. Set aside for the meat filling. Meanwhile, place potatoes in a medium saucepan and add enough cold water to cover. Add a big pinch of salt and bring to a boil. Reduce heat to a simmer and cook uncovered until soft, 10-12 minutes. While the potatoes are simmering, check the rice. The mixture should begin to look like a porridge, with the grains intact. (This will act as a binder for the meat, as well as providing moisture.)
Cabbage: Prepare an ice bath. Bring a large pot of water to a boil; blanch the cabbage leaves in the boiling water for 2-3 minutes, or until pliable. Remove leaves and immediately plunge them into the ice bath to stop the cooking. Set aside on paper towels to dry. Meanwhile, check the rice mixture. When the rice has absorbed all the milk, spread it on a plate to quickly cool, 5 minutes. (Note: Rice can be prepared up to 1 day ahead.)
Meat filling: In a large mixing bowl, add beef, pork, eggs, sautéed onions, milk, a big pinch salt (about 1 teaspoon) and white pepper (about 1 teaspoon), and the cooled rice. Combine well with your hands, a whisk, or wooden spoon. (Alternatively, use a stand mixer with the paddle attachment on low speed.) To check the seasoning, fry a small bit of the meat mixture and taste it.
Assemble rolls: Preheat oven to 350 degrees F. Grease baking dish with 1 tablespoon butter. Carefully cut out 1 inch of the thick center vein from the leaves, so they will be easier to roll up. Place 3-4 tablespoons of the meat filling (depending on the size of the cabbage leaf) into the center of a leaf and, starting at what was the stem-end, fold the sides in and roll up the cabbage to enclose the filling (like a burrito). Place the roll seam-side down in the baking dish. Repeat with remaining leaves and meat, arranging the rolls side by side in rows. Drizzle agave syrup over rolls and bake, 20 minutes.
After 20 minutes, remove dish from oven. Pour enough broth over the rolls to come halfway up the sides of the dish. Place back in oven for another 20 minutes.
Sauce: Cabbage rolls are done when brown on top and the meat is cooked through. Remove cabbage rolls from the dish and strain the cooking liquid through a fine-mesh strainer into a skillet. Bring liquid to a boil and reduce by half, whisking occasionally, 5 minutes. Whisk in cream, add a pinch of salt, and continue boiling to thicken slightly, 1 more minute. (Sauce will be on the brothy side.) Meanwhile, drain the potatoes and place in a bowl; add 1 tablespoon butter and salt to taste.
Place cabbage rolls and potatoes on a plate; add a few dollops of lingonberry jam on the side. Drizzle sauce over everything. Serve.