Season the beef with salt and pepper on both sides.
Turn the sear/saute function on high and pour in the Olive Oil. Once the oil gets hot, add the beef and sear on all sides. This should take 10-15 minutes.
Move the beef over to one side of the pot and pour in the onions. Allow the onions to start to cook down a little bit, about 5 minutes.
Add the garlic, Worcestershire sauce, thyme, rosemary, beef broth, and tomato sauce to the pot and stir.
Place the bay leaf on top of the beef and then place the cover on the Ninja Foodi Possible Cooker Pro.
Slow cook on HIGH for 4 hours.
At the end of 4 hours, the beef roast should be tender enough to cut/shred with a fork. If the beef is still tough, continue to slow cook on high until tender.
Using All Other Slow Cookers:
Season the beef with salt and pepper on both sides.
Pour Olive oil into a large frying pan and once the oil gets hot, sear the seasoned beef on all sides. This should take about 15 minutes. Add the onions to the pan with the beef and saute for about 5 minutes, or until the onions become transluscent.
Move the seared beef, onions, and oil over to the slow cooker pot.
Add the garlic, Worcestershire sauce, thyme, rosemary, beef broth, and tomato sauce to the pot and stir.
Place the bay leaf on top of the beef and then place the cover on the slow cooker.
Slow cook on HIGH for 4 hours or on LOW for 8 hours.
At the end of the cooking time, the beef roast should be tender enough to cut/shred with a fork. If the beef is still tough, continue to slow cook until tender.
Video
Notes
Do you have to brown a roast before putting it in the slow cooker?You should always brown a roast before cooking it in the slow cooker, dutch oven, or on the stove top. Browning the meat helps to create a barrier that keeps the juices in while cooking. If you don't sear the meat, it is more likely to be chewy and dry. It only takes a couple of minutes, but makes a big difference.Is it better to cook a roast on high or low in a slow cooker?Roasts are best cooked slow and low. So, cooking the roast on low in a slow cooker will provide the most flavor and the most tender roast. But, if you don't have 8 or 9 hrs for the roast to slow cook, you can slow cook it on high for half the time.