Lucia's "Short & Thick" with tomatoes and ricotta - Pasta Grannies

Ingredients

• 400 g durum wheat semola rimacinata (fine semolina flour)
• 200 ml cold water
• 3 tbsp extra virgin olive oil
• 1 small red onion, thinly sliced
• 500 ml tomato passata
• 200g whole datterini tomatoes
• 200g fresh cow’s milk ricotta
• Salt, to taste