Roasted New Potatoes with Romesco Sauce

This classic Catalán sauce keeps for a few months in the refrigerator, so I try to keep a batch on hand at all times for spur-of-the-moment entertaining. It’s a perfect sauce to serve with roasted baby potatoes or fingerlings for appetizers. With the sauce made ahead, the only task is to roast the potatoes, and that is simple to do: just cut, roast, and bake.