Preheat oven to 350 F.
Line a baking sheet with parchment paper. Place the squash slices, drizzle 2 tbsp olive oil all over. Season with salt, freshly ground pepper and a pinch of dry oregano. Add some chili flakes if you like. Bake in the oven for 15-20 min or so, until squash slices have a light golden color and moisture is gone. When ready, remove from oven and let them cool.
In a frying pan add 2-3 tbsp light olive oil. In high heat fry the potato slices for approximately 1-2 min, both sides. Remove slices and place in a paper towel to absorb extra oil.
In a large pot add 2 tbsp extra virgin olive oil. In medium heat, add the onions, season with a pinch of salt. After 2-3 min add the garlic. Stir well. Add the tomato paste. Season with another pinch of salt, freshly ground pepper and 1-2 pinch of dry oregano. Stir well. Add 1-2 pinches of chili flakes. Stir well.
Add all the ground meat. Break it to smaller pieces as it sautés. Mix everything well. Add the wine. Allow the wine to evaporate a little for 2-3 min. Remove from heat and set aside.