Melt the butter with the oil in a frying pan over a medium heat, add the shallots and cook, stirring occasionally, for 5 minutes. Add the speck strips and cook, stirring frequently, for 2–3 minutes until crisp. Pour in the wine and simmer for 2 minutes until the mixture is slightly reduced.
Add the peas and mint and cook, stirring occasionally, for 5 minutes if using fresh peas, or 2 minutes if using defrosted frozen peas. Season with salt and pepper.
Meanwhile, cook the pasta in a large saucepan of salted boiling water according to the packet instructions until al dente. Drain quickly, then toss into the frying pan with the pea mixture. Serve immediately with a scattering of Parmesan shavings, garnished with mint leaves.