To cook pasta: bring a large pot of water to a boil. Add pasta and cook until al dante, about 8 minutes.
To cook shrimp: meanwhile, heat olive oil in a 12-inch skillet over high heat.
Once shimmering, add shrimp in one layer and cook until opaque and just cooked through, about 2 minutes, turning half way through.
Remove onto a clean plate and cover to keep warm.
To make the sauce: reduce the heat to medium low and melt 1 tablespoon of butter in now empty skillet.
Add garlic and cook until fragrant, about 30 seconds, stirring frequently.
Add chicken broth (or pasta water) and lemon juice and cook until reduced by half, about 4 minutes.
Add remaining 2 tablespoons of butter and stir to melt. Season with salt and pepper to taste
Add shrimp and pasta and toss to combine.
Stir in parsley and serve immediately.