Combine the breadcrumbs and heavy cream in a small bowl; stir with a fork until all the crumbs are moistened. Set aside.
Heat the oil in a small skillet over medium heat. Add the onion and sauté for about 5 minutes, until softened. Remove from the heat.
In a large bowl, combine the ground beef, veal, pork, onion, honey, and egg, and mix well with your hands. Season with salt and pepper to taste. Add the breadcrumb-cream mixture and mix well.
With wet hands (to keep the mixture from sticking), shape the mixture into meatballs the size of golf balls, placing them on a plate lightly moistened with water. You should have about 24 meatballs.
Melt the butter in a large skillet over medium high heat. Add the meatballs, in batches if necessary, and cook, turning frequently, for about 7 minutes, until browned on all sides and cooked through. Transfer the meatballs to a plate, and discard all but 1 tablespoon of fat from the skillet.
For the sauce
Return the meatball skillet to the heat, whisk in the stock, cream, preserves, and pickle juice, and bring to a simmer. Season to taste with salt and pepper.
Return the meatball skillet to the heat, whisk in the stock, cream, preserves, and pickle juice, and bring to a simmer. Season to taste with salt and pepper.