1. Rinse the prawns thoroughly under cold water. Remove the legs and separate the heads from the tails. Slice the heads in half lengthwise and set both parts aside.
2. In a wide frying pan, gently heat 3 tablespoons of extra virgin olive oil with a clove of garlic and a sprig of thyme.
3. Add the prawn heads and tomato concentrate then stir-fry over medium heat for a few minutes, pressing them lightly to release their juices. Once fragrant and lightly browned, deglaze with white wine, allowing it to evaporate completely.
Add the chili and the cherry tomatoes. Cook until the tomatoes soften and begin to break down, stirring occasionally. Remove the prawn heads, the garlic and the chili, season to taste and add a few basil leaves, allowing to infuse.
4. In a separate pan, heat a drizzle of extra virgin olive oil and quickly stir-fry the prawn tails until just cooked through and lightly golden. Set aside and keep warm.
Cook the spaghetti al dente in salted boiling water according to package directions.
5. Drain and transfer to the cherry tomato sauce. Finish cooking in the pan, stirring with a little pasta water and extra virgin olive oil to create a silky emulsion. When the pasta is perfectly coated, add the prawns, some extra basil leaves and grated lemon zest.
Plate immediately and dress with some extra virgin olive oil.