Preheat your oven to 425 degrees Fahrenheit. Line a large, rimmed baking sheet with parchment paper for easy cleanup.
In a small bowl, whisk together the melted butter, minced garlic, lemon juice, Italian seasoning, salt, and pepper to create the garlic butter sauce.
Place the trimmed asparagus on one side of the prepared baking sheet. Drizzle with olive oil and toss lightly to coat.
Place the shrimp on the other side of the baking sheet. Pour about two-thirds of the garlic butter sauce over the shrimp and toss gently to coat completely.
Arrange the shrimp and asparagus in a single layer on the sheet pan, ensuring the shrimp are not overlapping.
Bake for 8 to 10 minutes. For extra crispiness on the shrimp, switch the oven to broil for the last 1 to 2 minutes, watching closely to prevent burning.
Remove the pan from the oven. Drizzle the remaining garlic butter sauce over the asparagus and shrimp.
Garnish with fresh chopped parsley before serving immediately.
Notes
For the crispiest shrimp, pat the shrimp dry with paper towels before tossing them in the sauce.
Do not overcrowd the sheet pan; use two pans if necessary to allow the shrimp to roast rather than steam.
If you prefer a stronger garlic flavor, add one more clove of minced garlic to the sauce.