Place meat in a large plastic bag. Measure flour and pour into the bag with the meat, and shake to coat.

Heat olive oil in a large skillet over medium-high heat. Add stew meat, and cook until evenly browned on the outside. Transfer to a slow cooker along with the carrots, potatoes, celery, garlic, and onion. Add tomatoes.

In a bowl, stir together 2 cups of boiling water, 2 tsp of bouillon paste, and 1 tsp Worcestershire sauce; pour into the slow cooker.

Cover and set the crockpot to Low, and cook for 8 hours, or high for 5 hours. Meat should be fork tender when done.