Layer the potatoes and then carrots in the crock of a 6.5 to 8 quart slow cooker. Cover, but do not turn on yet.
Combine the flour, paprika, salt, and pepper in a zipper top bag, close, and shake to combine. Open the bag, add the beef cubes, and shake to coat evenly. Remove the beef from the bag, shake off excess flour, and set on a plate. Heat 2 tablespoons of bacon fat in a large skillet over medium high heat. Add a single layer of beef cubes, taking care not to overcrowd the pan. Let the beef cubes rest on the one side, undisturbed, until you can lift one and it is brown on the bottom, rotate the cubes to brown on all sides. Use a slotted spoon or tongs to transfer the beef cubes to the slow-cooker, and repeat with remaining cubes, adding more bacon fat if needed.
While the beef is browning, whisk together the beef broth or stock, wine, tomato paste, fish sauce or soy sauce. When all of the beef has been browned and added to the slow cooker, return the pan to the heat and pour in the liquid ingredients, scraping the pan to release any flavourful fond from the pan. As that comes to a boil, scatter the garlic slices, onion wedges, quartered mushrooms, thyme sprigs, and bay leaf over and among the beef cubes. Once the liquids reach the boiling point, pour it over the contents of the slow-cooker, cover, and cook on HIGH for 3 to 4 hours, or until the beef, carrots, and potatoes are tender. Remove the bay leaf and thyme sprigs (if you used them). Stir in the frozen peas, replace the lid on the slow-cooker and cook for 10 minutes, or until the peas are hot all the way through.
Just before serving, crumble the reserved crispy bacon over the top of the bowl. Garnish with parsley and chives, if desired.