To a crockpot, add the wild turkey meat, bay leaves, marjoram, and thyme. Pour in enough stock to cover the turkey by a few inches. Cover the slow cooker with the lid. Cook on the high setting for around 6 to 8 hours or until fork-tender.
Once the turkey is tender, remove it from the crockpot and place it in a large bowl. Shred the meat and discard any bones or tendons. Set Aside.
Reserve 1.5 cups of the cooking liquid and set aside. Empty the remaining cooking liquid from the crockpot (you can save it for another use).
Make the sauce. Heat a medium-sized pot over medium heat. Add the onions, season with a pinch of salt, and cook until tender, about 5 minutes. Add the garlic and cook for 2 minutes. Pour the tomatoes, chipotles, and adobo sauce into the pot. Partially cover the pot and simmer for 5-8 minutes or until the mixture has slightly thickened. Remove from the heat. Pour the turkey, the sauce, and the 1.5 cups of reserved cooking liquid into the crockpot. Cover and cook on high for one hour.
Season with to taste with salt, sugar, and more adobo sauce if you like.