Potato Gratin with Sweet Peppers and Tomatoes
Why This Recipe Works
For our potato gratin recipe, we found that the variety of potato mattered less than that the potatoes were sliced consistently. Uniform slices between 1/16 to 1/8-inch (easily obtained using a mandoline) yielded a gratin with distinct slices of potato bathed in a velvety sauce. As for the liquid used in a gratin recipe, we tried making gratins with milk, half-and-half, heavy cream, broth, and water. Our favorite liquid turned out to be chicken broth. Gratins made this way had just the right balance of saturated potato and saucy liquid, without overwhelming the taste of the potato or other ingredients in the dish.