Prep the potatoes: Rinse and halve the baby potatoes.
Pat dry so they roast up tender instead of steaming into mush.
Season the potatoes: In a bowl, toss potatoes with half the ranch seasoning, half the garlic and onion powder, a pinch of salt, and a drizzle of olive oil. This helps the seasoning cling and keeps them from sticking.
Optional—sear the beef: Heat a skillet over medium-high with 1–2 tablespoons olive oil. Pat beef cubes dry, sprinkle with salt and pepper, and sear in batches for 1–2 minutes just to brown the edges.
This step adds flavor but isn’t required.
Layer in the slow cooker: Add seasoned potatoes to the bottom. Scatter seared (or raw) beef over the top.
Mix the sauce: In a measuring cup, combine beef broth, Worcestershire, the remaining ranch seasoning, garlic powder, onion powder, smoked paprika, and black pepper. Stir well, then pour over the beef and potatoes.
Add butter: Dot the top with butter pieces.
This enriches the sauce and keeps everything juicy.
Cook: Cover and cook on Low for 6–7 hours or High for 3–4 hours, until the beef is tender and potatoes are easily pierced with a fork. Chuck will take a bit longer than sirloin.
Finish and taste: Stir everything gently. Taste the sauce and adjust salt or pepper.
If you want a thicker sauce, remove the lid for the last 20–30 minutes on High, or whisk 1 teaspoon cornstarch into 2 teaspoons cold water and stir in, cooking for 10–15 minutes.
Garnish and serve: Sprinkle parsley or chives over the top. Serve straight from the crockpot with a side salad, steamed green beans, or crusty bread to soak up the sauce.