Gently mix the Potato, Squash Puree, Plain Flour, Potato Flour and both the whole Egg Yolk together in a bowl and season with Salt and Pepper.
Cut off a small piece and drop in to boiling water for 2 mins to test the consistency and seasoning.
Adjust the seasoning if needed, add a little more Plain Flour if the mix it too wet.
Roll the mix in to 20g balls then mark with a folk into shape.
In a pan add the remaining 50g of Squash Puree, Butter, Water and a drizzle of Olive Oil, boil together mixing occasionally until they have reduced to form a thick sauce.
Add the Gnocchi to a pan of boiling salted water for 3 mins then allow to drain quickly before dropping them in to the sauce and add the Sage, cook in the sauce for 2 mins and serve.
Finish with nuggets of Gorgonzola and broken Walnuts scattered on top.