How to make
Melt the butter with the oil over very low heat. Leave it to cool to body temperature.
Beat the eggs and sugar, add fat, condensed milk and pumpkin puree (boiled and pureed pumpkin). Beat with the mixer, until a homogeneous mixture is obtained and then continue by hand.
Sift the flour along with the baking powder into the liquid mixture. Stir with a spatula, until it is completely absorbed. Add the crushed nuts and a pinch of salt. Fill about 12-14 paper muffin cups, which are placed in a muffin tin.
Fill 3/4 of their volume. Put half a walnut in each muffin and press it lightly - almost the whole nut should sink.
Bake the muffins in a preheated oven at 360°F (180°C) for about 25 minutes - check them with a wooden skewer, in order to see if they are ready. Remove them from the muffin tin and leave them to cool.
Beat the pumpkin puree with the cream cheese and powdered sugar, until a creamy mixture is obtained. Pour it into a piping bag and pipe it out on the muffins.
The pumpkin muffins with walnuts and cinnamon are ready.