Beef with vinegar

1 cup boiling water 1 beef bouillon cube 1/4 cup balsamic vinegar 2 tablespoons light brown sugar 1 teaspoon olive oil 12 ounces beef tenderloin , fat[...]

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[...]