Preheat the oven to 400 degrees F (200 degrees C). Place 24 baguette slices onto a baking sheet.
Bake in the preheated oven until toasted, 15 to 20 minutes. Remove from the oven and let cool.
Heat oil and butter in a large pan over medium-high heat. Stir in savory, basil, and thyme; cook for 1 minute. Add shallots and cook until transparent, 5 to 7 minutes. Stir in garlic and cook, being careful not to burn, about 1 minute more.
Saute shrimp in the same pan over medium to medium-high heat until they are bright pink on the outside and the meat is opaque, 2 to 3 minutes per side. Transfer shrimp quickly to a separate dish; do not overcook.
Pour limoncello and lemon juice into the same pan and cook over medium heat until mixture is reduced by about half, 7 to 9 minutes. Add heavy cream gradually. Season with salt and pepper. Add shrimp back into the pan and heat, stirring to coat, 2 to 3 minutes.
Spoon 1 shrimp with sauce onto each baguette slice. Serve.
