Preheat a standard oven to 325°F or a convection oven to 300°F.

Coat garlic cloves with oil and wrap them in foil. Place on sheet pan.

Bake until garlic is soft and golden, 25 to 30 minutes. Mash garlic cloves with a fork until it forms a paste.

While garlic is roasting, in a stock pot over high heat, fill about ¾ of the way with water and bring to a boil. Add linguine and return to a boil.

Boil until al dente, 7 to 12 minutes.

Drain. Rinse with cold water and drain again. Set aside until ready to use.

In the same stock pot, over high heat, add vegetable broth, roasted garlic, lemon juice, and lemon zest and bring to a boil.

Combine water and cornstarch in a small bowl and whisk until well blended. Whisk cornstarch slurry into boiling broth mixture. Continue whisking until the broth thickens. Reduce heat and simmer for 5 minutes.

While broth is simmering, heat oil in a large sauté pan over medium – high heat. Add shrimp, onions, scallions, and garlic. Sauté for 2 minutes.

Pour in broth. Add black pepper, red pepper, and salt and bring to a simmer for 1 to 2 minutes.

Add pasta, zucchini noodles, and parsley and mix well with tongs. Cook until shrimp are opaque, approximately another 2 to 3 minutes.

Top with parmesan cheese and serve.