Ingredients
1 tablespoon neutral oil (like avocado oil or vegetable oil), plus more to grease pan
1 pound sweet Italian sausage, uncased
1 1/3 cups minced shallot (from about 2 large or 3 medium shallots)
1 jalapeño, minced (optional)
1 1/3 chopped scallions, green and white parts divided
8 large eggs
1 cup whole milk
1 teaspoon kosher salt, plus more as needed (I use Morton; you can scale up to 1 3/4 or 2 teaspoons if you use Diamond Crystal)
1/4 teaspoon freshly ground black pepper, plus more as needed
2 cups shredded melty cheese (such as cheddar, Gouda, or Monterey Jack), divided
1 (30-ounce) bag frozen shredded hash browns (unthawed), divided
2 tablespoons finely chopped chives
2 tablespoons finely chopped basil
1 cup crème fraîche
Instructions
  1. In a large skillet over medium-high heat, heat the oil until shimmering. Add the sausage and thoroughly brown sausage, crumbling into bite-sized pieces as it cooks. Remove with a slotted spoon and set aside, discarding all but 1 tablespoon or so of rendered fat.
  2. Reduce the heat to medium and add the shallot. Sauté for 4 to 7 minutes, stirring occasionally, until translucent and beginning to brown around the edges. Add the jalapeño (if using), as well as the scallions’ white parts and all but 2 tablespoons of the green parts. Sauté another couple of minutes until the scallions’ white parts have softened enough that you could easily break them into rings with a cooking utensil. (Don’t bother doing this—just use it as a check.) Add 2 tablespoons of water, and scrape up all the browned bits stuck to the bottom of the pan as the water evaporates.
  3. Remove the skillet from heat and set aside, allowing it to cool while you heat the oven to 350°F and grease a 9x13-inch pan with oil. Mince the remaining 2 tablespoons of scallion greens and mix those, as well as the chives, basil, and a pinch of salt, into the crème fraîche, and set aside.
  4. In a large bowl, gently whisk the eggs, milk, salt, pepper, and 1 cup of the shredded cheese. And roughly two-thirds of the frozen hash browns, the sautéed shallot mixture, and the browned sausage, and stir to combine. Pour into the prepared pan, cover with foil, and bake for 45 to 55 minutes, until the casserole has set and the center feels firm to the touch, with a little wiggle. Let the remaining hash browns thaw while it cooks, and pour off any liquid.
  5. Turn on broiler to preheat while you remove the foil from the pan and sprinkle remaining hash browns and cheese over the top, along with a few pinches of salt and pepper. Put the pan on top of a cookie sheet to catch any bubbling cheese—so it doesn’t end up on your oven floor—and place under the broiler, keeping a close eye to avoid burning. Broil for 3 to 7 minutes, until the top is crispy and browned. Remove from the oven. Run a knife around the inside edge of the pan before slicing and serving. Serve individual portions topped with dollops of herby crème fraîche and hot sauce.