Cut beef stew meat into bite-size pieces if needed
Pat the beef dry
Season the beef with salt and pepper
Dredge the beef in flour if desired
Heat oil in a skillet
Brown the beef on all sides
Place chopped onions, carrots, and potatoes in the slow cooker
Add the browned beef on top
Add minced garlic
Add beef broth
Add tomato paste if desired
Add Worcestershire sauce
Add bay leaves and thyme
Stir gently to combine
Cover and cook on low for 7 to 8 hours or on high for 4 to 5 hours
Add peas or green beans during the last 30 minutes if desired
Remove bay leaves before serving
Taste and adjust seasoning with salt and pepper
Serve hot