Sweet Potato Hash with Sausage & Eggs
2 pounds yellow onions (about 2 large)
1 tablespoon unsalted butter
1 pound fresh Italian sausage or chorizo
3 pounds sweet potatoes (about 3 large potatoes, ideally organic)
6 large garlic cloves
2 long stems fresh rosemary
3 tablespoons olive oil
1 tablespoon kosher salt, plus more to taste if necessary
Freshly ground black pepper
8 or more large eggs
Kosher salt and freshly ground black pepper
Parmesan cheese, to serve
To make the hash: Heat the oven to 450°F. Peel the onions and cut them in half lengthwise, then cut them into thin half-moons. Cut the half-moons in half. Melt the butter in a skillet over medium-high heat. When it foams up add the onions and sprinkle lightly with salt. (Don't worry if they are crammed into the pan; they will rapidly cook down.) Lower the heat slightly and cook the onions for about 30 minutes, stirring occasionally, and lowering the heat further if they seem to be burning. Cook them until they are very dark brown and caramelized.
Meanwhile, put the sausage in another skillet and brown over medium-high heat, chopping it up into fine crumbles with a spatula. Cook the sausage for about 10 minutes, or until browned and beginning to crisp. Drain away any excess fat.
While the onions and sausage are cooking, chop the unpeeled sweet potatoes into cubes that are about 1/2-inch to a side. Finely mince the garlic and rosemary leaves, and toss them in a large bowl with the sweet potatoes. Toss with the olive oil, kosher salt, and a generous helping of black pepper.
When the onions are dark brown and the sausage is beginning to get crispy, stir these into the sweet potatoes as well. Line a large baking sheet with foil or parchment paper, and spread out the sweet potato mixture evenly. Roast the sweet potatoes for 30 to 45 minutes (roasting time depends on the size and uniformity of the sweet potato chunks, as well as the variety of sweet potato you buy) or until they are soft and browned.
If not serving immediately, cool the hash and refrigerate for up to 3 days.
To serve: Heat the oven to 425°F. Spread a relatively thin layer of the (already cooked) sweet potato hash in a baking dish, such as a cast iron skillet or a 9x13-inch baking dish. You can also bake in individual ramekins. Make small wells in the sweet potatoes and crack in large eggs. Sprinkle lightly with salt and pepper.
Bake for 10 to 20 minutes, or until the sweet potatoes are hot and the eggs are baked through. (Test the eggs by prodding them with a fork to check the firmness of the white and the yolk; baked eggs are deceptive in that the white often looks much less cooked than it really is.)
Serve immediately, with shavings or sprinkles of Parmesan cheese, if desired.