These are a fun play on classic potato leek soup, equally yummy in autumn alongside a bowl of butternut squash soup as they are at a summer BBQ. They go beautifully with any kind of herbal aioli - I like adding chives to mine. —Hallie Meyer
Peel potatoes and cut into 2 inch cubes. Boil potatoes in a large pot of salted water for 30 minutes, or until just fork tender. Place potatoes in the food processor with tablespoon of butter and pulse until mashed.
Meanwhile, trim leek, dice, and wash in a bowl of cold water, allowing the dirt to sink to the bottom. Place leek pieces on a dry paper towel, and melt remainder of butter in a medium skillet over medium heat. Sweat leeks in the butter with salt and pepper until soft, about 6 minutes.
Add leeks to the food processor, add eggs, cheese, and pulse till combined. Transfer mixture to a bowl and refrigerate for at least 30 minutes.
In a large rimmed skillet, heat 2 inches of vegetable oil. In a baking dish, combine panko and polenta, season with salt, and whisk. Roll teaspoons of chilled croquette batter in the polenta and breadcrumbs and fry in oil until golden on both sides, about 2 minutes per side. Place finished croquettes on a paper towel lined platter and top with fried sage or fresh rosemary.