Add in onions and saute for 10-15 minutes until golden and softened.
½ large Onion
Season with salt & black pepper. Stir in tomato paste and cook for 2-3 minutes until starting to deepen in colour.
1 tbsp Tomato Paste, ½ tsp Salt, ½ tsp Black Pepper
Stir tomato passata. Allow to simmer for 20 minutes until slightly thickened.
300 g Tomato Passata, 8-10 g Fresh Basil
In the meantime, bring a large pot of water to boil and season generously with salt. Cook pasta according to package instructions. Reserve ¼-⅓ cup of Pasta Water.
250 g Spaghetti
Stir in butter and a pinch of sugar. Cook until the butter has melted into the sauce.
½-1 tsp Sugar, 1 tbsp Butter
Toss in cooked pasta, together with a splash of reserved pasta water.
Add the fresh basil and top pasta with Parmesan Cheese. Serve immediately.
8-10 g Fresh Basil
Notes
Italian tomato varieties/brands would be a good pick for good quality tomatoes for the recipe.
Tomato Passata is preferred for the recipe due to its smoother texture. If using tinned chopped tomatoes, you'll have to double the simmering time in order for the chopped tomatoes to break down into a thick sauce. The flavours in tinned chopped tomatoes also tend to be less intense than that in tomato passata.
Add fresh basil only at the end of the cooking process. Otherwise, basil has a tendency to turn bitter when being cooked for too long.
The butter and reserved pasta water help the sauce to bind with the pasta.