Use paper towels to thoroughly pat dry the pieces of stew meat. Set aside.

On a large plate, or in a large, shallow bowl, combine the flour, 1 1/2 teaspoons salt, and the pepper. Place the pieces of stew meat on the plate and lightly dredge with the flour mixture.

Meanwhile, heat the butter and olive oil in a large dutch oven over medium-high to high heat. Once hot, add the pieces of stew meat, browning on both sides. You may need to do this in 2-3 batches so as not to overcrowd the pan. Once the pieces are browned on both sides (they will not be fully cooked through - that is ok), remove to a clean plate.

Once all of the meat is browned and set aside, add the onion to the pan and cook for 2-3 minutes, until beginning to turn soft and translucent. Add the garlic, and cook for just another minute.

Pour the hard cider into the pot, using a wooden spoon to scrape the browned bits up off the bottom of the pot. Allow to cook for 1-2 minutes, then add the stock. Add the mushrooms, parsley, thyme, bay leaf, Worcestershire sauce, and return the meat to the pot. Bring to a simmer, turn the heat to low, cover and simmer for 1 1/2-2 hours, until the meat is cooked through and tender and the broth is reduced and flavorful. Add the carrots and sweet potatoes; simmer, uncovered, for another 20-30 minutes, until the carrots and potatoes are cooked through.

At this point, remove the bay leaf and take inventory of your broth. Does it seem thick enough, or does it need to be a bit thicker? If you would like it thicker (and I always do), use a ladle to spoon about 1/3 cup of the broth to a separate bowl. Whisk in 1 1/2 tablespoons of cornstarch until smooth, then return to the pot and stir; the stew should thicken up very quickly.

Taste for seasoning - you will likely need to add another teaspoon or so of salt, perhaps a couple more grinds of pepper.

Serve warm. Will keep in the fridge, covered, for 3 days, or in the freezer for 3 months.