Rub roast all over with salt and pepper and place into a slow cooker. Place the butter on top of the roast and the pepperoncinis around it. Carefully pour the beef broth around the roast, and not over the top. Cover with the lid.
Cook on low for 8-10 hours, or on high for 5-7 hours. (Low heat is preferable as it will give you more of a tender result.)
Shred meat into chunks and serve with rice or mashed potatoes, spooning the juices over the top. Or, stuff into tacos or burritos.
Notes
Timing Guide: Cook on low for 8–10 hours (2.5-3 hours per pound) or high for 5-7 hours. (Low heat will give you more of a tender result.) A 3-pound roast takes about 8 hours on low.
Liquid is Essential: Use at least 1 cup of liquid (beef broth, pepperoncini juice, or combination) to keep this lean cut moist and tender.
Low Heat is Best: Cook on low rather than high when possible. High heat can make this lean cut tough and dry.
Let It Rest: Rest for 10–15 minutes after cooking before slicing or shredding to keep the juices inside the meat.
Slice Against the Grain: Always slice perpendicular to the muscle fibers for the most tender results.
Classic Flavor Swap: Skip the pepperoncini and use onion soup mix, garlic, onions, or herbs (rosemary, thyme) for traditional pot roast flavor.
Adding Vegetables: Add potatoes, carrots, or other root vegetables during the last 3-4 hours so they don't get mushy. Cut into 2-inch chunks.
Easy Gravy: Pour juices into a saucepan, whisk in 2 tablespoons cornstarch mixed with 2 tablespoons cold water, and simmer until thickened. Or use flour instead.
Storage: Store leftovers in an airtight container with some juices. Refrigerate up to 4–5 days or freeze up to 4–6 months.
Doneness Cue: The roast is done when it's fork-tender and easily shreds apart. For slicing, aim for 145–160°F internal temp.
Don't Overcook: Avoid leaving the roast on "keep warm" for hours after cooking, as it can dry out.