Roast the bell peppers on stove top or bake them for 20-30 minutes on a preheated oven in a greased tray until the outer skin get charred and the flesh becomes soft.
Wrap them on a kitchen towel or foil and allow it to sweat for another minutes.
Meanwhile add oil in a pan; cook the onion and garlic with a pinch of salt till the onion starts to turn golden at the edges.
Peel off the charred skin; remove the stem and the seeds. Chop them in to large pieces and grind it along with onion and garlic into a smooth paste.
Cook the pasta with 6 cups of water and salt. once it cooked soft drain the water and rinse with cold water.
In a wide pan add oil; once the oil is hot add the all purpose flour once it get heated up add the milk and allow it to boil; it starts to thicken.
Now add the ground bell pepper sauce to make a creamy bell pepper sauce. Once the sauce starts to thicken switch off the gas and add the spaghetti or pasta of your choice.
Season with salt and pepper. If you wish add some Italian herbs too for more flavour.
