First, in a shallow dish, add your flour along with the onion powder, garlic powder, salt, pepper, and paprika.
Next, whisk the ingredients together to combine them thoroughly.
Then, lightly dredge the steaks in the seasoned flour mixture and set aside.
Meanwhile, in a large skillet over medium-high heat, melt your butter as you prepare to brown the steaks.
Once the butter is melted, add your steaks to the pan and quickly brown them on each side. Remember, you're just looking for a little color, not to cook the steaks through.
After browning, transfer the steaks to the slow cooker.
Add the carrots, celery, and onion on top of the steaks.
In a small bowl, whisk together the garlic, brown sugar, tomatoes, Worcestershire sauce, and brown gravy mix to create the sauce.
Pour the liquid mixture into the slow cooker.
Finally, cover the slow cooker and cook on low for 6–8 hours or on high for 4–6 hours, until the meat and veggies are tender.
Serve!