Gather the ingredients.
Thaw the shrimp according to the package directions, and remove tails if necessary. Drain the shrimp well and set aside.
In a large saucepan over medium-high heat, combine the butter and olive oil and heat until foaming.
Add the garlic and onion to the pan and sauté, stirring frequently, until the vegetables are crisp-tender.
Add shrimp and stir well.
Cover the pan and simmer for 1 to 2 minutes or until the shrimp are pink and curled and thoroughly heated.
Remove the pan cover and add the lemon juice, salad dressing, and peas
Cook and stir over medium heat or until everything is heated and blended.
Serve the shrimp scampi immediately over hot cooked rice and enjoy!