Put the olive oil in a Dutch oven or flameproof casserole with a lid and place over medium heat. Add the bacon and cook, stirring occasionally, until it is crisp and has given up most of its fat, about 10 minutes. Remove with a slotted spoon, add the meat, and raise the heat to medium-high. Cook, turning the cubes as they brown and sprinkling them with salt and pepper, until the meat is brown and crisp all over, at least 10 minutes. Remove with a slotted spoon.
Reduce the heat to medium and add the chopped onion, thyme, bay leaves, garlic, and parsley, along with some more salt and pepper, and cook, stirring occasionally, until the onion softens, about 5 minutes. Remove with a slotted spoon, then add the mushrooms and pearl onions and cook, stirring occasionally, until lightly browned, 5 to 10 minutes; transfer with a slotted spoon to a separate bowl. Add the wine and let it bubble for a minute, then return the meat to the pan, along with the chopped onion mixture.
Cover and adjust the heat so the mixture simmers gently for about an hour, then return the mushroom–pearl onion mixture, along with the bacon. Re-cover and continue to cook until the meat is tender, adding a little more liquid if the mixture threatens to dry out. Depending on the meat, the dish could be done in as little as 30 minutes more or in three times as long. Taste and adjust the seasoning, then garnish and serve or cover and refrigerate for up to 2 days before reheating.
