Begin by trimming any excess fat from your boneless chuck roast. This helps reduce greasiness in the final dish.
In a small bowl, mix together the onion powder, garlic powder, and pepper. Rub this seasoning blend all over the roast, ensuring it is well coated.
In a large skillet, heat the vegetable oil over medium-high heat. Once hot, add the seasoned roast and sear it for about 4-5 minutes on each side until browned.
Transfer the seared roast to the slow cooker. Add the peeled garlic cloves, beef broth, pepperoncini juice, soy sauce, dried minced onions, beef bouillon, dried parsley, chives, dill, oregano, bay leaf, and whole pepperoncini.
If you’re adding carrots and baby red potatoes, place them around the roast in the slow cooker.
Cover the slow cooker and cook on low for 8-10 hours or high for 4-6 hours, until the roast is fork-tender and flavorful.
Once the roast is done, remove it from the slow cooker and let it rest. In a saucepan, melt the butter over medium heat. Whisk in the flour to create a roux, cooking for 1-2 minutes until golden.
Gradually add in 2 cups of the beef broth from the slow cooker, whisking continuously until thickened.
Slice or shred the roast and serve it with the rich gravy over the top. Enjoy it with the carrots and potatoes for a complete meal!