Heat a large skillet with olive oil. While it's heating up, toss the cubed beef in flour to coat. Add to the hot pan and cook until well browned, then transfer to the slow cooker with a slotted spoon. Leave the oil and juice from the beef in the pan.
To the same skillet, add the onions and celery. Scrap the bottom of the pan to pick up the beef tidbits and sautee the veggies for just a few minutes. You're not cooking them all the way, just releasing flavor! Add to the slow cooker.
One more time to the same pan, add a little more oil or butter. Cook down the cabbage for about 8 minutes. This helps kickstart its cooking and gives more room in the crockpot for all the add-ins.
While the cabbage is cooking down, add the remaining fresh veggies, seasonings, bases (or broth) with water, garlic, and all the canned veggies minus peas. Then toss in the cabbage when done cooking.
Once everything is added to the crock pot it should be packed to the max full. I usually wait before stirring when everything is softer and will make less of a mess.
Cover and allow to cook for 5-6 hours until the potatoes and carrots are tender. Within the last 20-30 minutes, add in the peas and stir in the slurry (optional). Turn down to low. Serve and enjoy!