In a pan heat some butter and add dry red chillies, garlic and roughly chopped onions.
Once the onions are golden brown add roughly chopped tomatoes and cook until soft.
Now add spices (red chilly powder, coriander powder and garam masala) ,cashews and salt. Mix well and cook for a minute.
Add 1 cup of water and cook for another 10 minutes. Off the flame and let the mixture cool.
In a blender, add the tomato mixture to make a smooth paste.
In a thick bottom pan heat some butter, add all purpose flour (maida) and fry for 1 minute.
Lower the flame and add 1 cup of milk. Keep stirring continuously until the milk is thick. Once the milk is thick add the tomato paste and keep stirring until the sauce starts boiling.
Finally add boiled pasta, chopped capsicum and coriander leaf.
Adjust sauce with salt, black pepper and water if needed.
Serve pasta in makhani sauce hot.