
Mix 1 cup stock with tomato paste and flour in slow cooker, then mix in remaining stock. Brown beef, put in slow cooker. Sauté onion and garlic, reduce wine by 75%, add to slow cooker. Add herbs, Worcestershire, salt, pepper, stir, then add carrot, celery and potato. Slow cook 10 hours on low or 6 hours on high, serve over mash!
Sauce thickener first - Pour about 1 cup of beef stock in the slow cooker with the flour and tomato paste. Mix to combine until lump free using a rubber spatula - it will be a thin batter consistency. Pour in remaining beef stock and mix (if you see pesky lumps, use a whisk).
Sear beef - Sprinkle and toss the beef with the salt and pepper. Heat the oil in a large non-stick pan over high heat. Brown the beef aggressively in 2 or 3 batches (don't crowd the pan). Transfer straight into the slow cooker, leaving the fat behind.
Sauté onion - Add the onion and cook, stirring regularly, until softened. Add garlic and cook for another 30 seconds until it's golden and smells amazing.
Massively reduce red wine (flavour flavour flavour!) - Pour the wine in slowly (careful, it will sputter). Simmer rapidly, stirring every now and then, until reduced but 75%, about 1/2 cup. Pour wine and onions into slow cooker.
Everything else - Add the stock cube, Worcestershire sauce, bay leaves, thyme, salt and pepper. Stir well, then add the carrots, celery and potato. Do your best to stir again (it's hard, there's a lot of stuff!)
Slow cook - Push any exposed beef under the liquid, any veg above the liquid will mostly be submerged by the end (liquid level rises plus meat / veg soften). Slow cook on LOW for 10 hours or HIGH for 6 hours. (Note 6) The meat should be fork-tender.
Finish and serve - Stir peas in, leave for 2 minutes to thaw and heat up (they're already cooked). Serve stew over mash!