Chicche della nonna with tomato sauce

Ingredients

• 800 g red potatoes
• "00" wheat flour as needed
• 500 g spinach
• 100 g mixed cow's and sheep's milk ricotta
• 100 g grated Parmigiano Reggiano
• 1 egg
• Salt as needed
• 3 tablespoons extra virgin olive oil
• 1 onion
• 1 shallot
• 1 carrot
• 200 g canned peeled tomatoes
• Basil
• 1 knob butter