Cook ziti about 2 minutes less directions state; drain and set aside.
Preheat oven to 350F/180C.
Heat a large, deep oven-proof skillet over medium heat. Add the oil and 1 tbs of the butter and heat until butter is bubbly.
Add the garlic and cook until fragrant. Add the shrimp, parsley and dill. Cook until shrimp turns pink. Remove the shrimp from the pan and keep warm.
In the same pan, melt the remaining butter. Whisk in the flour and stir until no lumps remain. Cook for 3 minutes. Slowly whisk in the chicken stock, whisking constantly to avoid lumps. Whisk in the half-and-half and cook until it begins to bubble.
Add the drained tomatoes, lemon juice, grated cheese, salt and pepper. Taste for seasoning and add more salt and pepper if desired.
Stir in the reserved shrimp and cooked ziti. Top with mozzarella cheese.
Transfer pan to the oven and bake for 10 minutes, or until cheese is melted.
For EU/UK readers--"half-and-half" is an American dairy product which is 50% whole milk and 50% light/single cream. Whole (full-fat) milk can be substituted as stated in the recipe.