In a small bowl, combine salt and steak seasoning.
Drizzle each side of beef with olive oil and 1 tbsp. of seasoning mixture.
Sear beef in a large pan over medium-high heat until brown. Flip beef over and repeat on other side.
Place the beef in the slow cooker.
In a large bowl, mix vegetables with 2 tbsp. of olive oil and the remaining 1 tbsp. of seasoning mix.
Saute the vegetables in the same pan as the beef. Cook until browned, about 5 minutes, stirring occasionally.
Pour the veggies into the slow cooker. Add 1 cup beef broth, cover and cook 9 hours on low or 6 hours on high.
Once everything is cooked, use a turkey baster to remove the juices from the slow cooker and put in a small saucepan. Heat pan over medium heat until boiling.
In a small bowl, whisk together flour and remaining 1/2 cup beef broth. Add this to the boiling juices.
Whisk continuously for 2 minutes until thickened. Season with salt and pepper.
Plate the beef and vegetables and pour over the sauce.