California Chuck Roast

3.5-4 lbs beef chuck roast
Assorted vegetables: I used about 6 carrots, cut into 1-inch pieces; 3 or 4 stalks of celery, prepared the same way; 2 red bell peppers, in unscientific large-ish chunks; and 8 small-medium red potatoes, quartered.  You can also use sweet potatoes, winter squash, onions, etc…..
Sauce:
1 medium yellow onion, diced finely
3/4 cup finely diced celery
1 cup ketchup (we use a brand without high fructose corn syrup)
3/4 cup water
2 tablespoons each: brown sugar, Worcestershire sauce, apple cider vinegar, and lemon juice
1 teaspoon dry mustard
1/2 teaspoon salt
1/4 tsp black pepper (I usually use a little extra, though, because I like it)

In the insert of a slow cooker, mix all the ingredients for the sauce until combined.  Add the meat and vegetables and ladle some of the sauce over the top of everything to coat well.  Cover and cook on Low for 8-10 hours.  This should definitely be served with some sort of bread for soaking up the sauce, or cornbread if you’re feeling super-domestic.