Optional - Use a medium-size skillet and add a bit of oil to it and then sear the stew meat on all sides before adding to the slow cooker. This is a personal preference, I do not do this. If you do not, just move to the next instruction.
Season the stew meat with salt and pepper then place in the bottom of the slow cooker.
Add in the broth, bay leaf, paprika, garlic, Worcestershire sauce, potatoes, carrots, celery, and bouillon cube.
Cover and set to LOW for 8 hours.
Whisk together the cornstarch and water to dissolve the cornstarch, then whisk this mixture into the stew.
Let it sit for about 5 minutes with the lid on and warm to get it thickened.