In a large skillet over medium heat, melt 1 tablespoon butter and olive oil. Add shrimp, lemon slices, garlic, and crushed red pepper flakes, and season with salt.
Cook, stirring occasionally, until shrimp is pink and opaque, about 3 minutes per side.
Remove from heat and stir in remaining butter, lemon juice, and vegetable broth. Season with salt.
Toss shrimp with sauce. Garnish with parsley before serving.