Preheat and prep the squash. Heat the oven to 400°F (200°C). Halve the spaghetti squash lengthwise and scoop out the seeds. Drizzle the cut sides with 1 tablespoon olive oil, season with salt and pepper, and place cut side down on a baking sheet lined with parchment.

Roast until tender. Bake 35–45 minutes, depending on size, until the flesh easily shreds with a fork. It should be tender but not mushy. Let it cool for 5 minutes, then use a fork to pull the strands into “spaghetti.” Pat dry with paper towels if the strands look watery.

Pat the shrimp dry. While the squash roasts, pat shrimp dry with paper towels. Season lightly with salt and pepper. Dry shrimp sear better and stay juicy.

Build the scampi base. In a large skillet over medium heat, add 1 tablespoon olive oil and 1 tablespoon butter. When the butter melts, add garlic and red pepper flakes. Cook 30–60 seconds until fragrant—don’t brown it.

Sear the shrimp. Add the shrimp in a single layer. Cook 1–2 minutes per side until just pink and opaque. Transfer to a plate to avoid overcooking.

Deglaze and sauce. Pour in the white wine (or broth) and simmer 1–2 minutes, scraping up any browned bits. Add remaining 2 tablespoons butter and stir until the sauce turns glossy. Stir in lemon zest and 1–2 tablespoons lemon juice.

Toss with squash. Add the spaghetti squash strands to the skillet and toss to coat in the sauce. Return shrimp and any juices to the pan. Warm through for 1 minute. Taste and adjust salt, pepper, and lemon.

Finish and serve. Turn off the heat and stir in parsley. Serve with extra lemon wedges and a sprinkle of Parmesan if you like. For a bolder finish, add a small pinch more red pepper flakes.