Put the sieved flour in a large bowl with a pinch of salt, make a hole in the middle, as if it were a volcano. whisk the spinach (cooked and well drained) with an egg and oil. once a homogeneous cream is obtained, transfer it to the hollow made in the flour and add the other two eggs and start mixing with a fork ONLY THE EGGS AND THE SPINACHS.
When the eggs are well mixed begin to incorporate the flour. always stir with a fork until the dough is dry and crumbled. at this point turn on a lightly floured paino and start kneading with your hands until a homogeneous and elastic dough is obtained, it will take at least 10 minutes. if the dough is sticky, add a little more flour, but little at a time. when the pasta is ready, roll it in a film and let it rest at least 30 minutes out of the fridge. after 30 minutes the dough will be ready to be rolled out with a rolling pin or with the machine. this green pasta is traditionally used to make lasagna in the oven, but it is also excellent for tagliatelle or ravioli.