Beef with whites

2 tablespoons hot pepper sauce (I use Frank's RedHot ) 3 tablespoons white vinegar , divided 1/4 teaspoon cayenne pepper 2 teaspoons extra-virgin olive oil 1[...]

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[...]