In a large skillet or dutch oven add the olive oil over medium-high heat.
When the pan and oil are hot, place the chuck roast in the hot oil and cook for a minute or two until the side facing down on the pan, is brown. Then turn the roast and repeat for each side until all sides are brown.
Remove the roast and place it in the slow cooker.
Add the potatoes, onions, and carrots.
Pour the broth and Worcestershire over the roast and vegetables.
Add the taco seasoning, ranch seasoning and Italian or Greek Seasoning.
Cook on low for 8 - 10 hours.