Beef with potatoes

4 medium red potatoes, each cut into 8 wedges 1/4 cup water 1/2 red onion , thinly sliced 1 lb roast beef 1 pint grape tomatoes , cut in half lengthwise 9[...]

3 large russet potatoes , scrubbed 1 tablespoon olive oil 1 medium onion , chopped 1/2 lb lean ground beef 1 teaspoon Worcestershire sauce 1/4 cup tomato[...]