When making filled pasta, whether ravioli, tortellini or a large raviolo, any air trapped inside the parcel will expand rapidly the moment it hits boiling water, causing the pasta to burst and the filling to spill out. This is especially dangerous with a raviolo encasing a liquid egg yolk, where a single burst means the entire dish is lost. To prevent this, press gently around the mound of filling, working from the centre outward to push any air pockets toward the edges, then seal the pasta firmly with your fingertips. Marcus Wareing emphasised that this step cannot be rushed. Matthew Ryle recommended making at least two ravioli as insurance against this inevitable risk.