Heat a large ovenproof dish over a medium heat. Add the pine nuts and toss in the pan until toasted, transfer the pine nuts to a pestle and mortar, bash until roughly bashed.
Add the oil to the same pan followed by the onion and tomatoes, stir for 6-8 minutes until slightly softened. Put the butter in the pan and stir until bubbling and golden, add the lemon zest and penne and toss to coat the penne in the butter. Stir through the tomato sauce and stock, allow to simmer for 15 minutes over a low heat, stir constantly to prevent sticking.
Once the pasta is cooked stir through the baby spinach until wilted. Tear in chunks of the mozzarella and stir through. Season and then serve in wide bowls with the basil leaves and a crisp dry white wine.
Did you know World Vegetarian Day is observed annually around the world on October 1. #worldvegetarianday
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