Step 1

Bring a large pot of lightly salted water to a boil. Cook spaghetti in the boiling water, stirring occasionally, until tender yet firm to the bite, about 12 minutes. Drain and set aside.

Step 2

Meanwhile, whisk mayonnaise, chili sauce, lime juice, and Sriracha together in a bowl.

Step 3

Melt butter in a large soup pot over medium-high heat. Add shrimp and cook for 5 minutes. Add garlic and cook until fragrant, 1 more minute. Add cooked spaghetti and mayonnaise-chili sauce; toss to combine. Cook until sauce is hot, about 2 minutes. Turn heat off and let sit for 5 minutes to thicken.

Step 4

Divide among serving plates and garnish with chopped scallion.