Peel and chop the carrots, slice the onion, chop the celery, and quarter the baby potatoes.

Spread the chopped veggies across the bottom of the slow cooker to create a bed.

Place the 3 lb chuck roast on top of the vegetables.

In a medium bowl, whisk together 2 cups of water with the Italian dressing mix, Ranch mix, and brown gravy mix until the powders are fully dissolved and the mixture looks uniform.

Pour the seasoned water evenly over the roast and vegetables, then place the lid on the slow cooker.

Set to high and cook for 4 hours, or set to low and cook for 8 hours, until the roast is fork-tender and the potatoes are cooked through.

Remove the roast to a cutting board and either slice or shred with forks.

Stir the cooking liquid — if you want a thicker gravy, transfer some liquid to a small saucepan, whisk in 1–2 teaspoons cornstarch, bring to a simmer, and return to the slow cooker.

Return meat to the pot to warm through before serving.