Preheat your oven to 325F
Use a large oven proof pan with a lid, such as a Dutch Oven. Add a little oil over a medium/high heat and sear each side of the chuck roast.
Briefly remove the meat to a plate, and add the vegetables, garlic and herbs to the base of the pan, and add the meat back on top, then pour over the beef broth or water, season with salt and pepper.
It will take between 2.5 - 3.5hrs to cook this in the oven, depending on the size of your meat and the oven temperature.
--- HOW TO COOK POT ROAST IN A SLOW COOKER ---
Brown the meat on both sides in a large Cast Iron skillet with a little olive oil.
Add the vegetables, garlic and herbs to the Slow Cooker, and put the meat on top, then pour over the beef broth or water, season with salt and pepper.
Cook the meat on the HIGH setting for 3 - 5 hrs, or on the LOW setting for 6-8hrs, or until done.
--- HOW TO MAKE THE PALEO BEEF GRAVY ---
After the meat is cooked, pour off the broth from the pot roast and put it into a pan on the stove top.
Add two tablespoons of arrowroot or tapioca starch into a small bowl and mix with two tablespoons cold water.
Add half the arrowroot liquid mixture to the pan with the gravy while it's off the heat and stir it in.
Then cook it on a medium heat until the gravy is thickened. if you need it thicker add some more of the starch mixture and proceed as before.
If you are using arrowroot, it will thicken it just like cornstarch will, but I have found it can sometimes create lumps in the gravy. If that happens simply pour the gravy back through a sieve, and serve.
Serve with the canned green beans, warmed up in a sauce pan 5 minutes before serving.