Fill a pot with water, add the potatoes, bring it to boil and cook them about 45 minutes on medium heat.
Peel the potatoes while still hot.
Add the heavy cream, butter, salt, freshly ground pepper and nutmeg to taste. Using a potato masher, mash and stir the potatoes with the other ingredients. Add some milk until you reach a creamy consistency.
Separate the mashed potatoes into 3 bowls for each of the three flavours/colours: regular/yellow, spinach/green and red pepper/reddish orange. The part for the spinach should be smaller than the other ones because the spinach we’ll add will take some volume.
In the Regular: add 2 egg yolks, salt, black pepper and nutmeg to taste and stir them well with the masher.
In an ovenproof glass dish spread evenly a layer of these mashed potatoes
Preheat the oven at 180 C and bake it for 20 minutes until its top it is a bit golden brown.
Meanwhile, prepare the green – spinach layer:
Add the spinach, 2 egg yolks and salt and pepper to taste. Using a stick blender, mix them all together.
Spread carefully this green mashed potatoes in a layer on top of the yellow one. Bake it in the oven for another 20 minutes.
Now it’s time for the red layer: Mix the remaining mashed potatoes with 2 egg yolks and 3-4 salted red pepper paste.
Stir them all together, then spread it as the final layer in the baking dish.
In order to give it a more festive look, ornate it with some halved cherry/plum tomatoes.
Bake it for another final 20 minutes.
Take it out of the oven and let it cool down before serving.