Preparation:
1. We count on having mashed potatoes prepared and that we have reserved the 400 grams necessary for the recipe.
2. If this is not the case, you can prepare the puree without adding the water from cooking the potatoes or the liquid cream, since we want a puree that is as dry as possible.
3. Mix the puree with the egg yolks (failing that, a whole egg), the corn flour, the grated Parmesan cheese and the mustard.
4. Add salt and pepper to taste and stir well until you obtain a homogeneous mass.
5. Fill a pastry bag with a star nozzle with it and let it rest in the freezer for 10 minutes so that it takes shape.
6. Meanwhile, fill a frying pan halfway with oil and heat it over medium-high heat.
7. We drop strips of the puree onto the hot oil, gently to avoid splashes and burns.
8. We turn when the bottom is golden and fry on the other side before removing.
9. Drain the excess oil and serve immediately.
