Start by getting a pan of boiling water on the hob.
Whilst the water is coming to a boil, heat the 2 tablespoons of olive oil in a large heavy-based skillet/frying pan.
Cook the shrimp over high heat for just 2-3 minutes.
Remove the shrimp to the pan and set to one side.
Add the remaining olive oil to the skillet then cook the chopped onion for 2-3 minutes. Add the garlic and cook for a further minute.
Add the butter and as it melts add in the flour and stir well.
Slowly pour in the broth, whisking into the flour. The sauce will start to thicken.
Once the stock has been incorporated, add the zest and juice of the lemon, dried basil, and heavy cream.
Stir gently and place over very low heat.
Whilst the sauce is simmering, add a tablespoon of salt to the boiling pan of water, then cook the pasta as per the packet suggestions.
Add the pasta and shrimp into the hot sauce and gently lift everything together until well combined.
Stir through the cup of fresh spinach and thin the sauce as needed with the reserved cooking water.
Serve immediately garnished with parsley, black pepper, and maybe a little extra lemon zest.
