Ingredients
1tbspolive oil,plus more for the baking dish
3lbsspaghetti squash
2tspsalt
½tspground black pepper
1onion,finely chopped
1clovegarlic,minced
½cupjarred roasted red peppers,thinly sliced
2tbspchopped fresh sage leaves
3eggs
1cupwhole milk
3tbspflour
1½cupsgrated Jarlsberg,or baby Swiss cheese, (5 oz)
½cupfinely grated parmesan,(2 oz)
Preparation
Preheat the oven to 425 degrees F. Line a baking sheet with parchment. Brush or spray a shallow 2-quart baking dish with oil.
Cut the squash in half lengthwise and scrape out the seeds. Sprinkle with ¼ teaspoon salt and ⅛ teaspoon pepper. Place on the baking sheet with the cut sides down.
Bake for 30 to 40 minutes, or until the squash is tender when pierced with the tip of a paring knife. Remove from the oven and turn the squash so the cut sides are facing up.
Return the squash to the oven and bake for another 5 minutes to dry out any excess liquid. (The squash won’t necessarily look dry.) Remove and let cool.
In a large skillet set over medium heat, add 1 tablespoon of oil. Once the oil begins to shimmer, add the onions, ¼ teaspoon salt, and ¼ teaspoon pepper.
Cook, stirring occasionally, for 5 minutes or until softened. Stir in the garlic, red pepper slices, and sage. Cook and stir for another 1 minute. Transfer to a large bowl.
In a blender (immersion or countertop), pulse the eggs, milk, flour, ½ teaspoon salt, and ⅛ teaspoon pepper 3 to 4 times, or until the mixture is smooth.
With a fork, flake the squash strands into the bowl on top of the onions. Add 1 teaspoon salt and mix until combined.
Add the egg mixture, grated Jarlsberg cheese, and ¼ cup of the Parmesan to the squash. Stir to combine.
Bake the casserole: Transfer the squash mixture to the baking dish and sprinkle it with the remaining ¼ cup Parmesan. Bake for 40 to 45 minutes.
Let rest for 10 to 15 minutes before serving as a side dish or a vegetarian main.
