Prepare saffron tagliatelle. Put a pinch of saffron stamens in a small bowl and add 3tbsp boiling water. Leave to cool, to infuse colour and flavour. Strain through a fine sieve. Place flour and salt in a food processor, add oil, egg and egg yolks. Start motor and gradually add saffron infusion through feed tube. Stop processing as soon as the dough holds together. Turn dough onto a lightly floured work surface and knead until shiny and smooth. Wrap in foil or plastic wrap and chill for at least one hour. Cut dough in half and roll each piece very thinly. Cut into strips about 60cm long. Dry slightly then cut into tagliatelle. If you have a pasta roller, roll dough to setting 6, then cut into tagliatelle. Dry strips on rolling pings or a new broom handle. Prepare spring vegetable sauce. Toast pine kernels until golden under a hot grill or in a heavy dry frying pan. Chop rosemary. Slice courgettes. Trim spring onions but leave whole. Top and tail mange tout. Bring a large pan of salted water to the boil and add t tablespoon of olive oil. Place rosemary and cream in a large pan. Bring to boil and reduce slightly. Add broad beans and asparagus tips and cook for 30 seconds. Add spring onions, courgette rings and mange tout. Cook for a further 30 seconds. Stir in pine kernels. Add tagliatelle to pan of boiling water, return to boil and cook for just thirty seconds. Drain, rinse and add to vegetables and cream. Season to taste and heat through. Serve immediately garnished with chopped fresh chives, chive flowers and a sprig of rosemary.