Place a pan over a moderate-high heat and add a drizzle of olive oil. Once hot, add the chopped garlic and the stems from the basil – reserving the leaves for serving – and fry for a few minutes until softened
Add the tomatoes to the pan and turn off the heat, allowing the residual heat from the pan to soften and cook the tomatoes
Bring a large pan of water to the boil and add the anchovy sauce and spaghetti. Cook for 8–10 minutes until al dente
Meanwhile, reserve 4 of the softened tomatoes to serve and transfer the rest of the tomatoes to a blender. Blitz to create a thick tomato sauce, then pass the sauce through a fine sieve into a clean pan and gently heat through. Divide a third of the sauce between the serving bowls and return the pan to the heat
Drain the spaghetti, reserving the cooking water, and add the pasta to the pan with the remaining tomato sauce. Pour over enough of the cooking water to coat the pasta and cook gently for 2 minutes until fully combined
Place a nest of spaghetti on top of the sauce in each bowl and top with a piece of burrata, the reserved tomatoes and basil leaves. Finish with grated lemon zest to serve
