Roasted Potatoes with Charred Leek and Tarragon Aioli

What’s the secret to preparing potatoes that are tender on the inside and crispy on the outside? We use a two-step cooking process: first they’re simmered on the stovetop and then they’re roasted in the oven. To expose more of the surface area for crisping, we give them a gentle smash. And while the potatoes are practically perfect on their own, the accompanying garlicky aioli may be our favorite part. It’s embellished with tender melted leeks, fresh tarragon, and a big squeeze of lemon jui