Ingredient:

• 1 tablespoon canola oil
• 3-1/2 to 4 pounds boneless beef chuck roast, cut into 2-in. cubes
• 1 package (1 ounce) au jus gravy mix
• 1 package (1 ounce) ranch salad dressing mix
• 1/2 cup butter
• 1/2 cup pepperoncini
• 1/2 cup plus 1 tablespoon water, divided
• 1 tablespoon cornstarch